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Feed provided by Sleep Medicine Research Click to visit.engOptogenetics: Solving the Enigma of Sleephttp://www.sleepmedres.org/journal/view.php?number=106
Sleep is a crucial and evolutionarily conserved phenomenon, but the mechanisms that control sleepwake behavior and underlie sleep disorders are not yet fully understood. One major challenge for sleep research was the lack of technology that allows for cell-type- and circuit-specific investigation of neurons and neural circuitry. A decade ago, a novel methodology known as optogenetics was developed, which uses light to control specific cell types of neurons, either to activate or inhibit neuronal firings. The strength of optogenetics in neuroscience is the precise control of neuronal activities in millisecond scale and the ability to dissect the neural circuits and cell types to understand their functions. There have been substantial advancements made in the field of sleep research through the implementation of optogenetics. This review provides a brief introduction on the optogenetics and a consolidated summary of recent findings published in sleep research using optogenetics.Review ArticleSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=106Sleep and Anesthesiahttp://www.sleepmedres.org/journal/view.php?number=107
Since both anesthesia and sleep depress consciousness, bidirectional relationship between them has been further studied. Earlier findings have shown that they share electroencephalographic features and brain regions that are activated in both state of unconsciousness. Despite these similarities, medication-induced sedation provokes different outcome from natural sleep. Enlisting commonly used analgesic drugs, such as benzodiazepines, intravenous agents, benzodiazepine antagonists, opioids, and other adjuvants, the study is comprised of assorted case studies that are clinically applicable
or comparable. Acknowledging potential of analgesic drugs on sleep disorders including sleep deprivation, narcolepsy, circadian rhythm disorder, periodic limb movement disorder, and obstructive sleep apnea, the study underscores the clinical importance of studying both fields, sleep and anesthesia. In conclusion, the aim of this review is explaining the consequences of analgesic agents or sedatives on sleep and sleep disorders.Review ArticleSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=107Inferior Turbinate Surgery in Sleep-Disordered Breathing Patients with Nasal Obstruction: ...http://www.sleepmedres.org/journal/view.php?number=108
Sleep-disordered breathing (SDB) is characterized by the intermittent narrowing or collapse of the upper airway, including the nasal cavity, pharynx, and larynx during sleep. Nasal obstruction is one of the most frequent presenting symptoms in SDB patients, and therefore, medical treatments such as saline nasal irrigation, antihistamine, and topical nasal spray are the first recommendation. If the issue is not resolved, surgical treatments for nasal congestion are helpful in order to alleviate nasal obstruction, reduce snoring, and improve positive airway pressure compliance. Inferior turbinate surgery is one of the most commonly performed nasal surgeries (e.g., endoscopic sinus surgery, septoplasty, etc) used to improve nasal obstruction. There are various inferior turbinate surgical methods
including electrocautery, laser-assisted turbinoplasty, radiofrequency-assisted turbinoplasty, outfracture, submucous turbinoplasty, partial turbinectomy, and microdebrider-assisted turbinoplasty. Despite the development of these numerous approaches, no clear guidelines exist as yet to help determine the most appropriate modality for any individual patient. This is due to variation in pathophysiology and the degree and extent of the turbinate hypertrophy between patients. Consequently, a comprehensive understanding of these techniques, as well as the preservative concept of
functional nasal physiology, is critically important for all surgeons. We propose that the ideal inferior turbinate surgery would meet the following criteria: 1) be less invasive, 2) incorporate remodeling rather than excessive resection, 3) entail a submucosal versus superficial mucosal technique, 4) represent an individually selected technique that is best suited to the patient, and 5) address long term considerations rather than acute symptomatic relief.Review ArticleSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=108Cognitive Emotion Regulation Strategies and Insomnia or Other Psychiatric Symptoms among ...http://www.sleepmedres.org/journal/view.php?number=109
Background and Objective In South Korea, numerous people have died of lung injury from humidifier disinfectant. The objective of this study was to explore the association between cognitive emotion regulation strategies for victims of humidifier disinfectant accidents in Korea and their insomnia and other psychiatric problems.
Methods Among 196 subjects experiencing humidifier disinfectant-related interstitial pneumonitis, 40 subjects were assessed for their psychological states between June 2015 and May 2016. Their psychiatric symptoms were assessed using Insomnia Severity Index, Hospital Anxiety and Depression Scales, Patient Health Questionnaire-9, posttraumatic stress disorder Checklist for DSM-5, and Cognitive Emotion Regulation Questionnaire.
Results Subjects’ adaptive cognitive emotion regulation strategies were not correlated with rating scale scores. However, total score of maladaptive cognitive emotion regulation strategy was significantly correlated with all rating scale scores (all p < 0.01). Among maladaptive strategies, rumination and catastrophizing strategies were significantly correlated with severity of insomnia and other psychiatric symptoms.
Conclusions There was an association between victims’ maladaptive coping strategies and insomnia or other psychiatric symptoms. Thus, managing their coping strategies is necessary to help them survive in their current environment.Original ArticleSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=109Clinical and Polysomnographic Characteristics of Patients with Excessive Daytime Sleepinesshttp://www.sleepmedres.org/journal/view.php?number=110
Background and Objective Excessive daytime sleepiness (EDS) is a common symptom of
many sleep disorders. EDS is the result of disturbed sleep or the sleep-waking process. The measurement of the degree of EDS is important for diagnosis and for its correlation with the severity of sleep disorders. We aimed to compare the characteristics of sleep disorders which were related to EDS and to investigate whether the Epworth Sleepiness Scale (ESS) and multiple sleep latency test (MSLT) were correlated with the polysomnographic parameters.
Methods 387 patients with EDS who completed both polysomnography (PSG) and MSLT were included. The severity of EDS was evaluated using ESS. Comparison of demographic, PSG, and MSLT results according to the final diagnosis and obstructive sleep apnea (OSA) subgroups categorized by the Apnea-Hypopnea Index.
Results The ESS score did not differ between the groups, except for narcolepsy type 1 and delayed sleep phase disorder (p = 0.026). While the ESS score showed weak correlation with some PSG parameters, the mean sleep latency (mSL) of MSLT showed a significant and stronger correlation with PSG parameters. The mSL was significantly shorter in patients with severe OSA (4.6 ± 3.0, p < 0.001) while the ESS did not show any difference among the different severities of OSA (p = 0.754). Parameters which reflect OSA severity showed significant correlations with mSL.
Conclusions ESS is insufficient for reflecting differences in the types and severities of sleep disorders, so the objective parameters of PSG and MSLT are necessary for more precise diagnosis. There was significant but weak correlation with mSL in the case of ESS ≥ 10, indicating that ESS was a poor screening tool but could be a convenient tool for follow-up study, rather than repeated MSLT.<BR><p align='center'><img src='/upload/thumbnails/smr-main--1-32-.jpg' border=0></p>Original ArticleSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=110Differences in Trauma-Related Guilt in Females with History of Sexual Violence Based on ...http://www.sleepmedres.org/journal/view.php?number=111
Background and Objective Females with history of sexual violence report a high percentage of insomnia. Guilt is a common symptom among this group. This study investigated differences in trauma-related guilt cognition between females of sexual violence with high or low symptoms of insomnia.
Methods Participants were 43 females who reported having a history of sexual violence (mean age 26.56±7.81). All participants completed questionnaires about insomnia symptoms (Insomnia Severity Index, ISI), Posttraumatic stress disorder (PTSD) symptoms (PTSD Symptom Scale Self-Report), trauma-related guilt (Trauma-related Guilt Inventory, TRGI), depression (Beck Depression Inventory) and trauma-related information. The TRGI is consisted by global guilt, distress and guilt cognitions. Guilt cognitions can further be divided into Hindsight-Bias/Responsibility, Wrongdoing, and Lack of Justification subscales. Analyses were conducted using Pearson’s correlation coefficient and analysis of covariance.
Results Results indicated ISI scores were significantly positively associated with PSS scores (r = 0.620, p < 0.01) and the distress subscale of the TGRI (r = 0.488, p < 0.01), and negatively associated with guilt cognitions (r = -0.423, p < 0.01). 53.5% (n = 23) of the sample met criteria for clinical insomnia using ISI cut-off scores of 15. Participants in the insomnia group scored significantly lower in overall guilt cognitions (p < 0.001) and significantly higher in distress (p = 0.001) than the non-insomnia group after controlling for depression. Among the subscales of guilt cognitions, hindsight-bias/responsibility was significantly lower in the insomnia group (p < 0.001).
Conclusions Guilt can sometimes be adaptive in trauma patients as it may work as a catalyst in cognitively processing their trauma. Our results indicate that individuals with insomnia report lower guilt cognition. This may subsequently interfere with their ability to process the traumatic experience and effectively cope with their situation.Original ArticleSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=111Factors Associated with Disruptive Behavioral Symptoms in Idiopathic Rapid Eye Movement Sleep ...http://www.sleepmedres.org/journal/view.php?number=112
Background and Objective Little is known about the factors associated with disruptive behaviors in idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD). Thus, we report the demographic and clinical characteristics of iRBD patients with disruptive behaviors.
Methods Patients diagnosed as having iRBD through video-polysomnography were included in the present study. The REM sleep behavior disorder questionnaire-Hong Kong (RBDQ-HK) was used to divide participants into two groups according to the presence or absence of disruptive behaviors. Neuropsychological tests as well as the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Beck Depression Inventory (BDI) were also conducted.
Results Of 188 iRBD patients, 160 patients showed more disruptive behaviors and were of a younger age (66.8 ± 7.4 vs. 70.5 ± 6.0, p = 0.012), of a higher proportion of men (69.4% vs. 39.3%, p = 0.004), and showed lower Apnea-Hypopnea Indexes (AHI) (9.2 ± 0.9 vs. 17.8 ± 2.2, p < 0.001) than those without disruptive behavioral symptoms. No statistically significant differences in PSQI, ESS, BDI, or neuropsychological testing were found. In multiple logistic regression analysis, age ≥ 70 [odds ratio (OR) = 0.36, 95% confidence interval (CI) = 0.15–0.87, p = 0.023], male sex (OR = 2.80, 95% CI = 1.14–6.91, p = 0.025), and score of item 4 (violent or aggressive dreams) of RBDQ-HK (OR = 1.57, 95% CI = 1.17–2.12, p = 0.003) all showed a significant association with disruptive behaviors.
Conclusions Age < 70, male sex, lower AHI, and frequent violent or aggressive dreams are associated with an increased risk of disruptive behavioral symptoms in iRBD. Therapeutic plans including clonazepam medication should be individualized considering patients’ demographic and clinical features.<BR><p align='center'><img src='/upload/thumbnails/smr-main--1-46-.jpg' border=0></p>Original ArticleSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=112The Perceptions and Effects of Sleep Deprivation in a Department of Anesthesiologyhttp://www.sleepmedres.org/journal/view.php?number=113
Background and Objective Sleep deprivation has multiple pathophysiological, psychological and cognitive effects. The effects of sleep deprivation on anesthetists have been recognized both within and outside of the workplace. This study investigated the perceived effects of sleep deprivation on anesthetists. To document the longest time spent without sleep due to work schedule, to describe the perceptions of the effects of sleep deprivation and the degree of sleepiness and daytime fatigue symptoms using the Epworth Sleepiness Scale (ESS) and to describe measures taken by anesthetists to overcome sleepiness.
Methods A prospective, contextual, descriptive research design was followed for the study. A convenience sample of anesthetists completed a questionnaire regarding perceptions and effects of sleep deprivation and the ESS. Data were descriptively analyzed.
Results The mean [standard deviation (SD)] longest time spent without sleep due to work schedule was 31 (9.1) hours and all anesthetists felt that they had insufficient sleep due to work schedule, with 61 (57%) stating this occurred 1 to 2 nights per week. Effects of sleep deprivation included effects on academic development, feeling tired at work, difficulty in concentrating at work and feeling stressed or irritable. Dozing off in theatre both during a night call and a day shift at different frequencies were reported. Other effects on family and social life were described. The mean (SD) ESS score was 11.5 (4.4).
Conclusions Anesthetists reported perceptions of inadequate sleep and the subsequent effects both at work and at home. Further research to determine the extent of sleep deprivation amongst anesthetists in South Africa is suggested.<BR><p align='center'><img src='/upload/thumbnails/smr-main--1-53-.jpg' border=0></p>Original ArticleSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=113Are You Asking What Time Did Your Patients Go to Bed?: Getting the Short Sleep Onset Latencyhttp://www.sleepmedres.org/journal/view.php?number=114
A few patients diagnosed with insomnia attempt going to bed earlier to obtain adequate sleep and fall asleep less than 30 min, although they often complain about their inability to fall asleep easily. The aim of this study was to explore the association between short sleep latency and patients’ sleepwake pattern. All the 99 patients with primary insomnia who were under treatment with benzodiazepine or non-benzodiazepine gamma-aminobutyric acid (GABA) agonists as sleeping pills were selected. The time to take hypnotics, bedtime, sleep onset, and wake-up times were determined from medical records. Subjects who showed sleep latency of less than 30 min (SL ≤ 30, n = 56) were treated with hypnotics (10:46 pm) before going to bed (11:00 pm) later compared with subjects with sleep latency greater than 30 min (SL > 30 min, n = 43, hypnotic ingestion time, 9:46 pm; bedtime 10:10 pm). Duration from wake-up time to bedtime (WTB) was significantly longer in SL ≤ 30 group (16.5 ± 1.1 h) compared to SL > 30 group (15.8 ± 1.5 h). Long sleep latency was significantly correlated with old age, earlier ingestion of sleeping pills, earlier bedtime, and short duration of WTB (all, p < 0.01). Early bed time in the evening was not associated with short sleep latency. Patients with insomnia may find that delayed bedtime may promote faster sleep. Brief CommunicationSat, 30 Jun 2018 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=114Autoimmunity and Immunotherapy in Narcolepsyhttp://www.sleepmedres.org/journal/view.php?number=88
Narcolepsy is a neurological disorder characterized by excessive daytime sleepiness, cataplexy, hypnagogic hallucination, and sleep paralysis. Narcolepsy is caused by damage of hypocretin producing neurons in the lateral hypothalamus. The association of narcolepsy with HLA DQB1*0602 and high incidence following H1N1 pandemic in china, vaccination with pandemrix and an adjuvanted H1N1 vaccine suggests that pathophysiology of narcolepsy is involved in the immune system. This review focused on immunological associations and immunotherapy in narcolepsy.Review ArticleFri, 30 Jun 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=88STOP-Bang Questionnaire in Patients with Rapid Eye Movement Sleep Behavior Disorderhttp://www.sleepmedres.org/journal/view.php?number=104
Background and Objective The snoring, tiredness, observed apnea, and high blood pressure– body mass index, age, neck circumference, and gender (STOP-Bang) questionnaire is known as a simple but useful tool for the diagnosis of high-risk obstructive sleep apnea (OSA). However, the utility of STOP-Bang questionnaire in rapid eye movement (REM) sleep behavior disorder (RBD) populations is not validated. This study aimed to determine the diagnostic value of the STOP-Bang questionnaire in patients with RBD at high risk for OSA. Methods We collected data from 65 consecutive patients who were diagnosed with RBD in a tertiary sleep center (20 women; mean age, 64.3 ± 12.5 years). All the patients visited sleep center with complaints of abnormal behavior during sleep, and underwent testing with STOP-Bang questionnaire and polysomnography. The diagnosis of RBD was based on the International Classification of Sleep Disorders, second edition. We diagnosed OSA when apnea-hypopnea index (AHI) was at least 5/h. The receiver operating characteristic (ROC) curves were plotted. Results The mean AHI was 18.2 ± 16.5/h, and 75.4% (n = 49) had an AHI ≥ 5. The STOP-Bang (threshold ≥ 3) identified 70.7% of patients as high risk for OSA, and sensitivity, specificity, positive and negative predictive values were 81.6, 62.5, 87, and 52.6%, respectively. The area under the ROC curve (AUC) was 0.79 (p < 0.001). The STOP (threshold ≥ 2) identified 70.7% of patients at high risk for OSA, and sensitivity, specificity, positive and negative predictive values were 75.5, 87.5, 94.9, and 53.8%, respectively. The AUC was 0.86 (p < 0.001). A pairwise comparison of ROC curve between STOP-Bang and STOP was insignificant (p = 0.145). Conclusions In RBD population, the STOP-Bang or STOP questionnaire is a useful screening tool to identify patients at high risk for OSA.<BR><p align='center'><img src='/upload/thumbnails/smr-main--2-102-.jpg' border=0></p>Brief CommunicationSun, 31 Dec 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=104Using Mid-Sleep Time to Determine Chronotype in Young Adults with Insomnia-Related Symptomshttp://www.sleepmedres.org/journal/view.php?number=105
The Munich Chronotype Questionnaire (MCTQ) uses sleep behavior to assess chronotype, but the extent to which such sleep behavior based assessments might be useful in populations with sleep disorders, such as insomnia, is currently unclear. We thus systematically assessed sleep disorders, MCTQ and the Morningness-Eveningness Questionnaire (MEQ), another behavioral preferencebased assessment of chronotype, in 310 individuals. In a smaller substudy (n = 121), we compared the MCTQ to sleep diaries in insomnia patients and good sleepers. Insomnia patients had overall lower consistency in chronotypes compared to good sleepers on the MCTQ compared to the MEQ, which was also evident when compared to sleep diaries. As insomnia disorder is characterized by time gaps spent awake during the night due to difficulty maintaining sleep, there may be limitations in using mid-sleep time as an accurate indicator of chronotype in insomnia patients. Our study suggests that the MCTQ should be used in conjunction with another existing questionnaire or assessment tool when assessing chronotype in insomnia patients.Brief CommunicationSun, 31 Dec 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=105Introducing the Sleep Disorders Symptom Checklist-25: A Primary Care Friendly and Comprehensive ...http://www.sleepmedres.org/journal/view.php?number=90
Background and Objective With sleep disorders highly prevalent and associated with poor health outcomes, screening for sleep disorders in primary care could reduce the burden of chronic diseases and costs of health care. Currently, a brief comprehensive primary-care-friendly multiple-sleep-disorders screening instrument is not available. The Sleep Disorders Symptom Checklist (SDS-CL)-17, a single-page instrument, was developed to screen for six sleep disorders (insomnia, obstructive sleep apnea, restless legs syndrome/periodic limb movement disorder, circadian rhythm sleep-wake disorders, narcolepsy, and parasomnias) and evaluated psychometrically. SDS-CL-17 psychometrics are reported. The resulting development of a more comprehensive single-page 25-item instrument, the SDS-CL-25, based on validation study results is described. Approaches for clinical use of the SDS-CL-25 are recommended.
Methods A cross-sectional study using nested data from two previous research studies (n = 395 sleep clinic referrals and n = 299 community volunteers) was used. SDS-CL-17 subscale scores and physician diagnoses were analysed using receiver operator characteristic curves. Resulting cut-point scores determined sensitivities/specificities. Study subject interview data were used to assess patient-friendliness of the instrument.
Results Sensitivities/specificities for the diagnosed sleep disorders ranged from 0.64 to 0.88. Interviewees endorsed the instrument as user-friendly.
Conclusions While the SDS-CL-17 is useful, the SDS-CL-25 assesses for a much larger number of sleep disorders yet retains brevity and is therefore recommended for ongoing clinical use. Psychometric evaluation of the SDS-CL-25 continues.Original ArticleFri, 30 Jun 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=90Sleep Fragmentation Induces Activation of NOD-Like Receptor Protein-3 Inflammasome in Rat ...http://www.sleepmedres.org/journal/view.php?number=91
Background and Objective Continuous sleep is important for cognitive function; studies have shown that disrupted sleep has a deleterious effect on hippocampus-dependent cognitive function, but the exact mechanism is unknown. The inflammasome NOD-like receptor protein-3 (NLRP-3) has been reported to cause memory and cognitive dysfunction, but no studies have examined whether NLRP-3 is up-regulated in the hippocampus by sleep fragmentation (SF). Therefore, we investigated whether SF affected NLRP-3 activation in the rat hippocampus in a wheel-based SF model.
Methods We randomly divided 7-week-old male Wistar rats into 4-day SF, 4-day exercise control (EC), 8-day SF, and 8-day EC groups. SF was accomplished with a forced walking wheel with a 30-s on/90-s off cycle, and we set EC at 10 min on/30 min off. We performed Western blots to compare NLRP-3 expression levels, and we measured malondialdehyde (MDA) levels in the hippocampus with a commercial kit.
Results The SF group had more but shorter NREM bouts. Western blot analysis revealed that 4 and 8 days of SF up-regulated the expression of the NLRP-3 complex in the hippocampus including ASC, caspase-1, and IL-1β. Thioredoxin-interacting protein expression also increased more in the SF group, and the MDA level increases were greater in the SF groups than in the corresponding EC groups.
Conclusions SF up-regulates NLRP-3 in the hippocampus. Additional behavioral and mechanistic studies are required to clarify the role of NLRP-3 in the hippocampi of rats subjected to SF.<BR><p align='center'><img src='/upload/thumbnails/smr-main--1-26-.jpg' border=0></p>Original ArticleFri, 30 Jun 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=91Insomnia and Neuroticism are Related with Depressive Symptoms of Medical Studentshttp://www.sleepmedres.org/journal/view.php?number=92
Background and Objective Insomnia is very common in depression and especially medical students are easy to experience sleep disturbance because of their studies. Also depressive symptoms are closely related to stress. Stress is an interaction between an individual and the environment, involving subjective perception and assessment of stressors, thus constituting a highly personalized process. Different personality traits can create different levels of stress. In this study, we tried to explore the relationship between insomnia and depressive symptoms or stress of medical students, and whether their personality may play a role on this relationship or not.
Methods We enrolled 154 medical students from University of Ulsan College of Medicine. We used the Medical Stress Scale, the Multidimensional Perfectionism Scale, the Patient Health Questionnaire-9, the Academic Motivation Scale, the Insomnia Severity Index, and The revised NEO Personality Inventory (PI).
Results Insomnia severity, amotivation, medical stress, mental health index and neuroticism traits of NEO-PI significantly correlated with depressive symptom severity (p < 0.001). And stepwise linear regression analysis indicated insomnia, amotivation and neuroticism traits of NEO-PI are expecting factors for students’ depressive symptoms is related to (p < 0.001).
Conclusions Student who tend to be perfect feel more academic stress. The high level of depressive symptom is associated with insomnia, amotivation, academic stress in medical student. Moreover, personality trait also can influence their depressive symptoms.Original ArticleFri, 30 Jun 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=92The Effect of Morningness-Eveningness on Shift Work Nurses: Sleep Quality, Depressive Symptoms ...http://www.sleepmedres.org/journal/view.php?number=93
Background and Objective The purpose of this study was to investigate the effect of morningness-eveningness type on nurses relative to sleep quality, depressive symptoms and occupational stress.
Methods Data was collected using self-administering questionnaires by 257 three eight-hour randomly rotating shift system nurses at St. Vincent’s Hospital. Questionnaires were composed of baseline demographic data, Korean version of Morningness-Eveningness Questionnaire, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Beck Depression Inventory and Korean Occupational Stress Scale. Kruskal-Wallis H test and analysis of covariance were used to identify significant differences in sleep parameters, depressive symptoms and occupational stress according to morningness-eveningness type.
Results There was significant difference in Subjective Sleep Quality score (p = 0.018). Post hoc analysis revealed differences between eveningness vs. morningness (p = 0.001) in Subjective Sleep Quality score. There were tendencies in sleep efficiency, PSQI total score and ESS between morningness-eveningness type. However, there were no significant differences in total sleep time, depressive symptoms and occupational stress including eight sub-categories according to morningness-eveningness type.
Conclusions Eveningness type nurses revealed lower Subjective Sleep Quality and tendency for poor sleep efficiency, poor overall sleep efficiency and more severe daytime sleepiness than other type. However, morningness-eveningness were not decisive factors for total sleep time, depressive symptoms and occupational stress. Short-term medication, workers’ chronotypes consideration and naps before night shifts may be helpful in improving mental health and quality of life for shift nurses, especially for evening shifts.Original ArticleFri, 30 Jun 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=93Sleep Apnea Patient with Sustained Ventricular Tachycardia During Polysomnographyhttp://www.sleepmedres.org/journal/view.php?number=94
Standard in-lab polysomnography (PSG) is a relatively safe, common diagnostic procedure. Few reports have flagged cardiac events during PSG, but the recent study shows that adverse events during a PSG were uncommon. Here, we present a patient with obstructive sleep apnea who had a medical emergency (sustained ventricular tachycardia) during PSG.<BR><p align='center'><img src='/upload/thumbnails/smr-main--1-44-.jpg' border=0></p>Brief CommunicationFri, 30 Jun 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=94Research Ethics and the Future Direction of Sleep Medicine Researchhttp://www.sleepmedres.org/journal/view.php?number=100
EditorialSun, 31 Dec 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=100Adapting Cognitive-Behavior Therapy for Insomnia in Cancer Patientshttp://www.sleepmedres.org/journal/view.php?number=98
Insomnia disorder is common in patients undergoing cancer treatment. There is compelling evidence demonstrating that cognitive-behavioral therapy for insomnia (CBT-I) should be the initial treatment, but there has been insufficient research has been conducted among cancer patients. This population presents with unique physical and psychosocial health issues that may interfere with standard CBT-I and addressing these issues can play a role in improving treatment adherence and efficacy. We explore potential adaptations that can be made to standard CBT-I for cancer patients. Further research for this growing population is essential. Review ArticleThu, 21 Dec 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=98Trends of Public Interest in Sleep Disorders: Looking by Internet Searching Volumehttp://www.sleepmedres.org/journal/view.php?number=99
Background and Objective To investigate the trends of public interest in the sleep disorders by searching terms in Korea and English-language. Google and Naver offer the tools assessing Internet searching volumes that may represent public interest on search terms.
Methods Search terms were limited to Korean in Naver Trends and English in Google Trends. We use the keywords insomnia, sleep apnea, snoring, restless legs syndrome (RLS). A reference trend of dementia was compared.
Results The median Naver Trends score of insomnia [21.3, interquartile ranges (IQR), 17.9– 26.5] was consistently higher than that of dementia (11.7, IQR, 10.0–13.5), RLS (7.5, IQR, 5.9–9.3), snoring (7.3, IQR, 5.9–10.5) and sleep apnea (1.6, IQR, 1.2–2.0) January 2016–October 2017. The Naver Trends score of sleep disorders decreased over time. The median Google Trends score of dementia (49, IQR, 45–55) was higher than that of sleep apnea (42, IQR, 40–45), insomnia (36, IQR 34–38), snoring (24, IQR 21–28), and RLS (23, IQR, 22–27) January 2004–October 2017. The Google Trends score of snoring and insomnia increased over time, but RLS and sleep apnea decreased over time. However, when we matched the search period with Naver Trends, the trends scores of insomnia, sleep apnea, RLS, and dementia increased over time.
Conclusions The Naver Trends score of insomnia was higher than that of dementia, but those of sleep apnea, RLS was relatively low. To the contrary, the Google Trends score of dementia and sleep apnea was higher than that of insomnia.<BR><p align='center'><img src='/upload/thumbnails/smr-main--2-62-.jpg' border=0></p>Original ArticleThu, 21 Dec 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=99Sleep Patterns of Firefighters with Shift Working Schedules in Seoul Metropolitan Areahttp://www.sleepmedres.org/journal/view.php?number=95
Background and Objective Firefighters suffer from irregular and inadequate sleep, often due to their shift work schedule. The purpose of this study was to investigate the shift work schedules and their effects on the quality of sleep in Korean firefighters.
Methods This study included firefighters in the Seoul Metropolitan area, who participated in the “Firefighters’ Healing Camp” and answered questionnaires for their shift work schedules and sleep-related symptoms. Among 180 participating firefighters, 110 subjects completed detailed sleep questionnaires, which included the Pittsburgh Sleep Quality Index, the Insomnia Severity Index, the Epworth Sleepiness Score, the Stanford Sleepiness Score, the Fatigue Severity Scale, and the Berlin Questionnaire, and provided details of their shift work schedule and duration for the last 3 weeks.
Results Among 110 respondents, 78.2% self-reported sleep disturbance and approximately 60% of the participating firefighters had a certain degree of insomnia. Furthermore, more than 50% of the firefighters complained of excessive daytime sleepiness, with 31.8% having a risk of obstructive sleep apnea (OSA). The firefighters in the frequent night-shift (NS) working pattern (5 or more days for 3 weeks), showed significantly higher Pittsburg Sleep Quality Index global score than those in the infrequent (less than 5 days) NS group (8.8 ± 3.6 vs. 6.7 ± 2.7, p = 0.014). However, the frequent NS working pattern was not associated with excessive daytime sleepiness or OSA risk.
Conclusions The participating firefighters reported a high prevalence of various sleep problems. Frequent NS working may be responsible for poor sleep quality in firefighters.Original ArticleTue, 19 Sep 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=95Excessive Daytime Sleepiness and Its Risk Factors for Commercial Bus Drivers in Koreahttp://www.sleepmedres.org/journal/view.php?number=101
Background and Objective Recent research has found the high prevalence of excessive daytime sleepiness (EDS) among commercial bus drivers which may induce serious physical injury and economic damages. However, there are limited data revealing the risk factors of EDS among these workers. Therefore, we investigated the EDS in commercial bus drivers and its risk factors. Methods Self-report questionnaires were given to 842 city bus drivers in Suwon, Korea, that included demographic characteristics, the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Insomnia Severity Index, and Berlin Questionnaire. The logistic regression analysis was conducted to investigate the risk factors of EDS among commercial bus drivers. Results The average of body mass index and total sleep time of 304 responding drivers were 24.7 ± 3.2 kg/m2, 6.05 ± 1.51 hours, respectively. Among them, 13.2% reported an Epworth sleepiness score > 10. The majority of the responders reported suffering from poor sleep quality (68.4%) and 10.2% reported having a moderate to severe insomnia. The proportion of group with high risk for obstructive sleep apnea (OSA) was 26.7%. In multivariate regression analysis, only three variables, including poor quality of sleep, insomnia, and high risk for OSA, were significantly associated with EDS. Conclusions This study has shown a high prevalence of EDS and insomnia, poor quality of sleep and high risk for OSA as risk factors of EDS among commercial bus drivers in Korea.Original ArticleSun, 31 Dec 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=101The Optimizing Strategies for Prescription of Sleeping Pills for Insomnia Patientshttp://www.sleepmedres.org/journal/view.php?number=89
Many patients claim that they cannot sleep well despite ingestion of sleeping pills. In such cases, the physician should explore the reason why sleep disturbance persisted in patients despite administration of sleeping pills. We should consider patients’ age, gender, medical or psychiatric diseases, workplace, or sleep environment that may influence patients’ sleep and satisfaction with their hypnotics. However, prior to prescribing a hypnotic agent for patients with sleep disturbance, good sleep hygiene education should be provided first. Cognitive-behavioral therapy for insomnia is an important and effective treatment modality to improve patients’ sleep quality and reduce dosage of sleeping pills, but it is not easy for most general practitioners to learn and practice this modality. Therefore, we need to consider how to optimize the prescription of hypnotics for treating insomnia in order to prescribe hypnotics safely and appropriately at the lowest dosage. Physician should consider the mechanism of action of each hypnotic agent and prescribe proper hypnotics according to patients’ comorbid illness, insomnia types, or other underlying sleep disorders. Also, we should instruct the patients about when they should take their sleeping pills and we should monitor whether they have followed the instructions or not. Hospitalized patients are in a different sleep environment compared to outpatients, and therefore, we should also prepare modified management strategies for inpatients. In this review, strategies for optimizing the prescription of sleeping pills for insomnia patients will be discussed.<BR><p align='center'><img src='/upload/thumbnails/smr-main--1-8-.jpg' border=0></p>Review ArticleFri, 30 Jun 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=89Eating Behaviors and Appetite of Children with Adenotonsillar Hypertrophy: A Preliminary Studyhttp://www.sleepmedres.org/journal/view.php?number=102
Background and Objective Abnormal eating behaviors and decreased appetite are usually found in children with adenotonsillar hypertrophy (ATH). The aim of this study was to examine eating behaviors and appetite using Korean–Children’s Eating Behavior Questionnaire (K-CEBQ) in ATH children and compare the subgroups according to combined problems. Methods Parents of 147 children (boy 97, girl 50) aged 2.4–14.1 years (6.8 ± 6.86 yrs) completed a validated K-CEBQ from December 2015 to December 2016. Patients were categorized and compared between allergy (n = 41) and non-allergy (n = 104); with frequent upper respiratory tract infection (URI, n = 65) and without frequent URI (n = 82); with obstruction problems only (n = 57), with infectious problems only (n = 7) and with both problems (n = 83). Analyses were conducted to examine correlations between scores of the subscales, K-CEBQ and children subgroups. Results All subscales of K-CEBQ except food fussiness were not significantly different between allergy and non-allergy groups. However, food fussiness was significantly different between the two groups (p = 0.015). There were no significant differences in subscales of K-CEBQ for other comparisons. Conclusions ATH itself or sleep disordered breathing due to ATH might have a major contribution to appetite and eating behavior irrespective of allergy, recurrent URI, or surgical indications. Further study is needed to determine changes of appetite and eating behavior after adenotonsillectomy.<BR><p align='center'><img src='/upload/thumbnails/smr-main--2-81-.jpg' border=0></p>Original ArticleSun, 31 Dec 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=102Neuropsychiatric Symptoms in Patients with Idiopathic Rapid Eye Movement Sleep Behavior Disorderhttp://www.sleepmedres.org/journal/view.php?number=103
Background and Objective Idiopathic rapid eye movement sleep behavior disorder (IRBD) is a strong predictor of the development of synucleinopathies, including Parkinson’s disease. Neuropsychiatric symptoms are common in patients with Parkinson’s disease but have not been properly evaluated in IRBD. We used the Symptom Checklist-90-Revision (SCL-90-R) to evaluate the symptom profile of patients with drug-naïve IRBD. Methods Consecutive drug-naïve patients with video-polysomnography-confirmed IRBD that visited Kyung Hee University Hospital at Gangdong sleep clinic January 2009–November 2016 were reviewed. Age- and sex-matched healthy volunteers served as controls. Questionnaires evaluating sleep [Pittsburgh sleep quality index (PSQI) and insomnia severity index (ISI)] and depression [beck depression inventory-II (BDI-II)] were conducted with the SCL-90-R in IRBD patients and controls. Results Twenty patients with IRBD and 20 age- and sex-matched controls were analyzed. In IRBD patients, the mean age was 59.5, 55% were male, and the mean disease duration was 55.1 months. PSQI scores (5.7 ± 2.2 vs. 3.2 ± 1.4, p < 0.0001) and ISI scores (11.2 ± 8.7 vs. 4.1 ± 3.4, p < 0.0001) were higher in patients with IRBD than in the controls. Three IRBD patients (15%) had abnormal SCL-90-R T-scores over 70. The T-scores for phobic anxiety (p=0.009), interpersonal sensitivity (p = 0.011), psychoticism (p = 0.013), hostility (p = 0.014), anxiety (p = 0.020), and depression (p = 0.049) were higher in the patients. After adjusting for age, BDI-II scores were positively correlated with RBD disease duration (r = 0.484, p = 0.042) in IRBD patients. Conclusions The results of our study demonstrate that neuropsychiatric distress is more severe in patients with IRBD with no comorbidities than in otherwise healthy individuals.<BR><p align='center'><img src='/upload/thumbnails/smr-main--2-86-.jpg' border=0></p>Original ArticleSun, 31 Dec 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=103Insomnia and Parental Overprotection are Associated with Academic Stress among Medical Studentshttp://www.sleepmedres.org/journal/view.php?number=96
Background and Objective The purpose of this study was to explore particular aspects of the mental health status of medical students and to identify relationships among them.
Methods All 191 medical students from University of Ulsan College of Medicine were included in this study. Psychological parameters were measured with the Medical Stress Scale (MSS), Insomnia Severity Index, Korean-Parental Overprotection Scale, Patient Health Questionnaire-9 and Academic Motivation Scale.
Results Stressed students (MSS ≥ 28) had significantly higher scores on insomnia severity (5.8 ± 4.5 vs 4.4 ± 3.0, p < 0.05), depression (5.7 ± 4.5 vs 2.6 ± 2.4, p < 0.01), and amotivation (9.3 ± 3.3 vs 6.9 ± 2.2, p < 0.01) and lower scores of intrinsic motivation (3.5 ± 7.1 vs. 41.7 ± 7.2, p < 0.01) compared to non-stressed students (MSS < 28). Significant correlations were noted between several factors and Medical Stress Scores. Specifically, insomnia, depression, amotivation and maternal ‘face culture’ of parental overprotection, had independent and significant influences on academic stress reported by medical students (R<sup>2</sup> = 0.39, p < 0.01).
Conclusions Our findings revealed insomnia, depression, academic motivation and parental overprotection are relevant factors influencing stress in medical students. Current results provide insights for stress management including the importance of parenting intervention.Original ArticleTue, 24 Oct 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=96Assessment of Cancer-Related Dysfunctional Beliefs about Sleep for Evaluating Sleep Disturbance ...http://www.sleepmedres.org/journal/view.php?number=97
Dysfunctional beliefs about sleep may be associated with chronic sleep disturbance in patients afflicted with cancer over the trajectory of their battle with cancer. The objective of this study was exploration of the utility of assessing the sleep disturbances suffered by cancer patients possibly emanating from two cancer-related informationally valid but nonetheless dysfunctional beliefs: “My immune system will have serious problems if I don’t go to sleep at a certain time (question 1)” and “If I don’t sleep well at night, my cancer can recur or metastasize (question 2).” The scores for these beliefs were significantly correlated with insomnia severity [measured using the Insomnia Severity Index (p < 0.01)] and fear of disease progression [measured using the Fear of Progression Questionnaire (p < 0.01)]. The question 2 score also correlated with younger age (p = 0.01) and high depression scores assessed using the Patient Health Questionnaire-9 (p = 0.04). We believe the scores for these two cancer-related dysfunctional beliefs can be used to help evaluate sleep disturbances in cancer patients.Brief CommunicationFri, 03 Nov 2017 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=97Upper Airway Evaluation in Patients with Obstructive Sleep Apneahttp://www.sleepmedres.org/journal/view.php?number=74
<p>Obstructive sleep apnea (OSA) is a widespread disease of substantial social burden. As various surgical procedures are now developed to alter the offending anatomic abnormalities, identification of the exact problematic site with application of the most appropriate treatment including surgical procedure is essential for effective surgical treatment of OSA. To date, many techniques are available for the physician to assess and analyze the upper airway obstruction including radiographic cephalometry, sleep video fluoroscopy, computed tomography imaging, sleep magnetic resonance imaging, drug induced sleep endoscopy, multi-channel pressure measurements, acoustic reflectometry, and basic physical examinations. However there are still some controversies concerning the effectiveness and morbidity of each technique. Therefore, sleep medicine doctors should understand the characteristics of each tool with the pathophysiology of OSA. Herein, we review the clinical methods to evaluate the upper airway in terms of disease severity and treatment selection.</p><BR><p align='center'><img src='/upload/thumbnails/smr-main--1-1-.jpg' border=0></p>Review ArticleThu, 30 Jun 2016 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=74Effects of Continuous Positive Airway Pressure Treatment on Cognitive Functions in the Korean ...http://www.sleepmedres.org/journal/view.php?number=75
<sec>
<title>Background and Objective</title>
<p>Obstructive sleep apnea (OSA) in elderly is accompanied by cognitive decline. However, it is not well known whether these deleterious changes can be reversed by continuous positive airway pressure (CPAP) treatment. Therefore, we aimed to elucidate the effect of CPAP on cognitive function in the Korean elderly with OSA.</p></sec>
<sec>
<title>Methods</title>
<p>Forty-two patients (≥ 60 yrs) with moderate-to-severe OSA and 41 normal controls were enrolled, and divided into treated subjects with CPAP (n = 28) and non-treated subjects (n = 14). We performed baseline measurements of cognition using the Korean version of the consortium to establish a registry for Alzheimer’s disease neuropsychological battery. Additionally, digit span test, Stroop color and word test (SCW) and executive clock drawing task were applied. About 175.6 days later, second measurements of cognitive function were completed.</p></sec>
<sec>
<title>Results</title>
<p>OSA groups had higher body mass index than normal controls (t = 3.132, p = 0.002). In comparison of cognition, OSA groups showed more decline in digit span test (forward; t = −3.647, p = 0.001, backward; t = −7.925, p &lt; 0.001) with Bonferroni correction. In the OSA group, subjects with CPAP treatment were younger (t = 2.787, p = 0.008) and had a longer education years (t = 2.419, p = 0.020) than non-treated subjects. In comparison of cognition after CPAP treatment, they showed significant improvement in the executive function (SCW; F = 5.660, p = 0.023) after adjusting the age and education years, considering interaction effect with time and groups.</p></sec>
<sec>
<title>Conclusions</title>
<p>Short-term CPAP treatment could improve executive function, but might not be effective on other cognitions in the elderly with OSA. Future study with long-term CPAP is required to evaluate beneficial effects on cognitive dysfunctions in elderly with OSA.</p></sec>Original ArticleThu, 30 Jun 2016 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=75The Effectiveness of Prolonged-Release Melatonin in Primary Insomnia Patients with a Regular ...http://www.sleepmedres.org/journal/view.php?number=76
<sec>
<title>Background and Objective</title>
<p>Prolonged-release melatonin (PRM) might effectively increase patient satisfaction when administered to individuals older than 55 years old with primary insomnia who were not satisfied with their sleep even after their sleep-wake cycle schedule was set. We investigated patients’ satisfaction rate with PRM when they took it after their sleep-wake cycle was set.</p></sec>
<sec>
<title>Methods</title>
<p>Among 87 patients who were prescribed PRM at the sleep clinic, 44 patients with primary insomnia who complained of poor sleep quality even after adopting a set 7-hour sleep-wake schedule or taking sleeping pills 7 hours before wake-up time were selected their medical records were reviewed. We explored patients’ satisfaction rates with PRM after 3–4 weeks.</p></sec>
<sec>
<title>Results</title>
<p>Among the 35 subjects who completed follow-up, 23 (66%) reported an improvement in insomnia symptoms after taking PRM. Five subjects reported daytime sleepiness as treatment-emergent adverse events. Of the 25 subjects taking other sleeping pills at baseline and followed up, 11 (44%) reduced their sleeping pill dosage by at least 50%. Five subjects completely discontinued their previous sleeping pills after starting PRM.</p></sec>
<sec>
<title>Conclusions</title>
<p>We observed a high satisfaction rate with PRM when prescribed to patients with a regular sleep-wake cycle. We believe that the results of this study will help to optimize hypnotic prescription to insomnia patients.</p></sec><BR><p align='center'><img src='/upload/thumbnails/smr-main--1-16-.jpg' border=0></p>Original ArticleThu, 30 Jun 2016 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=76The Effect of Adenotonsillectomy on Growth in Prepubertal Childrenhttp://www.sleepmedres.org/journal/view.php?number=77
<sec>
<title>Background and Objective</title>
<p>To document the effect of adenotonsillectomy on prepubertal growth in children according to preoperative growth status and follow up period.</p></sec>
<sec>
<title>Methods</title>
<p>The clinical records of 161 prepubertal children with sleep breathing disorder who underwent adenotonsillectomy between 1998 and 2007 were assessed. The height, weight and body mass index (BMI) was converted to z-score (standard deviation scores) for their ages. Preoperative growth status was divided to three groups (less than 25th percentile, 25–75th percentile, and more than 75th percentile). The changes of weight, height and BMI were evaluated according to follow up periods and preoperative growth status.</p></sec>
<sec>
<title>Results</title>
<p>The slopes (Δz-score/year) of general parameters (height, weight, BMI) were not significant statistically. For height-for-age, &lt; 25th percentile group had significant increase of z-score by 0.155 per year (p = 0.009), but the other groups did not. For weight-for-age, z-score of 25–75th percentile group was increased by 0.119 per year (p = 0.010) and z-score of &gt; 75th percentile group was decreased significantly by 0.096 per year (p = 0.039). But for BMI-for age, the slopes of all groups were not significant statistically.</p></sec>
<sec>
<title>Conclusions</title>
<p>Adenotonsillectomy could make constant increase of height during prepubertal period for &lt; 25th percentile children. Also adenotonsillectomy make constant increase of weight for 25–75th percentile children, and make decrease of weight for &gt; 75th percentile children during prepubertal period. Adenotonsillectomy might have different effects on growth indices of children with sleep disordered breathing according to initial growth status.</p></sec><BR><p align='center'><img src='/upload/thumbnails/smr-main--1-21-.jpg' border=0></p>Original ArticleThu, 30 Jun 2016 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=77Accuracy of the Auto Scoring by the S9 CPAP in Patients with Obstructive Sleep Apneahttp://www.sleepmedres.org/journal/view.php?number=78
<sec>
<title>Background and Objective</title>
<p>Several continuous positive airway pressure (CPAP) devices currently in use automatically estimate and provide information of the residual respiratory events such as apnea-hypopnea index (AHI), apnea index (AI), and hypopnea index (HI). To compare the auto scoring of the residual respiratory events using the S9 CPAP device with simultaneous manual scoring and identify factors that are associated with difference between auto scoring and manual scoring in patients with OSA.</p></sec>
<sec>
<title>Methods</title>
<p>Patients with moderate to severe OSA titrated manually using S9 CPAP device were included. The correlation between auto scoring and manual scoring was assessed during an overnight standard in-hospital CPAP titration.</p></sec>
<sec>
<title>Results</title>
<p>Eighty-six patients with moderate to severe OSA were included. There was a strong correlation between auto scoring and manual scoring on AHI (r = 0.74, p &lt; 0.001), with a stronger correlation on the AI (r = 0.86, p &lt; 0.001), and a weaker correlation on HI (r = 0.56, p &lt; 0.001). Overall, S9 auto scoring tended to underestimate the AHI (mean AHI difference: −1.30) owing to the strong underestimation on HI. Higher BMI, higher AHI from diagnostic polysomnography, higher leakage and lower oxygen saturation were independent factors for greater difference between auto scoring and manual scoring.</p></sec>
<sec>
<title>Conclusions</title>
<p>Auto scoring showed strong correlation with manual scoring. However, auto scoring of S9 CPAP tended to underestimate the AHI, as compared to manual scoring. Characteristic features of severe OSA were associated factors for difference between auto scoring and manual scoring.</p></sec><BR><p align='center'><img src='/upload/thumbnails/smr-main--1-26-.jpg' border=0></p>Original ArticleThu, 30 Jun 2016 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=78The Sleeping Pill Prescription Rate for Inpatients at a General Hospitalhttp://www.sleepmedres.org/journal/view.php?number=79
<sec>
<title>Background and Objective</title>
<p>Hospitalized patients often suffer from sleep disturbance. Impaired sleep for inpatients is a multifactorial phenomenon, comprised of medical, environmental, and behavioral influences imposed by hospitalization. In such situation, inpatients are frequently prescribed sleeping pills. The aim of this study was to explore the pattern of sleeping pill prescription for hospitalized patients in a general hospital.</p></sec>
<sec>
<title>Methods</title>
<p>Located in Seoul, Korea, Asan Medical Center is a general hospital that oversees about 2100 to 2300 inpatients per day. We estimated the proportion of patients who were prescribed sleeping pills at admission and discharge from the hospital, excluding pediatric care units. In addition, we quantified the number of patients taking prescribed sleeping pills on the first day of each month of 2014.</p></sec>
<sec>
<title>Results</title>
<p>Among 118475 patients admitted to Asan Medical Center in 2014, 4205 (3.54%) were taking sleeping pills at the time of admission. In addition, 4652 (3.93%) patients were prescribed sleeping pills as a discharge medication, of which 2256 (1.90%) initiated hypnotics intake during hospital stay. Surveyed on the first day of every month of 2014, 7.3% to 10.0% of inpatients were observed to be taking sleeping pills.</p></sec>
<sec>
<title>Conclusions</title>
<p>The number of prescriptions of sleeping pills was found to increase with hospital stay. A palpable need for sleep hygiene education and the implementation of a hypnotics reduction program for inpatients is warranted.</p></sec>Original ArticleThu, 30 Jun 2016 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=79Superficial Vein Thrombosis as the Initial Manifestation of Protein S Deficiency in an ...http://www.sleepmedres.org/journal/view.php?number=80
<p>Protein S (PS) deficiency and narcolepsy have a similar pathomechanism in view of autoimmunity, and they can develop following an infection. However, there is no previous report of a patient with narcolepsy associated with PS deficiency and the relationship between these two diseases has not yet been investigated. PS deficiency may lead to coagulopathies, which can present as superficial or deep vein thrombosis and embolism. Therefore, here we describe a case of an 18-year-old man with narcolepsy who presented with superficial vein thrombosis associated with PS deficiency. Our case suggested that the development of PS deficiency and narcolepsy can be interrelated with each other.</p>Case ReportThu, 30 Jun 2016 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=80Narcolepsy: Association with H1N1 Infection and Vaccinationhttp://www.sleepmedres.org/journal/view.php?number=82
Epidemiological studies have demonstrated an association between H1N1 influenza infection and vaccinations. This article reviews the various studies, and suggests the biological mechanisms explaining why and how H1N1 influenza infection or vaccine stimulates the autoimmune response, thereby resulting in narcolepsy. Among the vaccines, the effect of Pandemrix was scrutinized more than other vaccines, due to its higher association with an increase of narcolepsy onset. The consequences of using other vaccines which contain same or different adjuvants as Pandemrix, were also analyzed.Review ArticleThu, 27 Oct 2016 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=82Prevalence of Insomnia among Patients with the Ten Most Common Cancers in South Korea: Health ...http://www.sleepmedres.org/journal/view.php?number=81
Background and Objective
The insomnia rate in cancer patients is nearly three times higher than that in the general population. Due to the distinct and diverse nature of cancer, the prevalence of insomnia is assumed to be affected by differences in primary cancer sites. In this study, we explored the prevalence rates of insomnia among the ten most prevalent cancers in South Korea using a national patient sample.
Methods
This was a 1-year cross-sectional study for the year 2011 using a national patient sample provided by the South Korean National Health Insurance. We selected all patients who had received International Classification of Disease, Tenth Revision (ICD-10) codes for the ten most prevalent cancers. To identify insomniacs, we included patients who had been diagnosed with ICD-10 codes or patients who had been prescribed with sleeping pills. The cancer and insomniac groups were subsequently merged and analyzed.
Results
Insomnia was most prevalent in lung cancer (15.2%), followed by non-Hodgkin’s lymphoma (9.2%), bladder (8.8%), colorectal (8.6%), stomach (8.0%), prostate (7.8%), breast (7.8%), cervix (7.8%), and liver (6.6%) cancers, and was least prevalent in thyroid cancer patients (5.8%). Within all cancer groups, insomniacs were significantly older than non-insomniacs. Insomnia predominance was not found in female cancer patients, which is in contrast to that typically seen in the general female population. In subgroup analysis, the prevalence of insomnia differed by both age and sex.
Conclusions
The prevalence of insomnia varied according to cancer type. Patients with lung cancer were the most prone to insomnia. Since clinical and psychological factors may influence prevalence of insomnia, these factors will need closer study in the future.<BR><p align='center'><img src='/upload/thumbnails/smr-main--2-48-.jpg' border=0></p>Original ArticleThu, 27 Oct 2016 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=81Restless Legs Syndrome and Morningness-Eveningness in the Korean High-School Studentshttp://www.sleepmedres.org/journal/view.php?number=83
Background and Objective
Restless legs syndrome (RLS) lowers the quality of sleep, and is characterized by symptoms that follow a circadian pattern. The aim of this study was to determine the relationship between RLS and morning-eveningness in Korean adolescents.
Methods
Of the 867 community-dwelling high school students, 590 subjects were included in this study. All participants completed self-report questionnaires, including demographic variables, particulars about menstruation, life style, sleep duration, RLS severity, Composite Scale, Epworth Sleepiness Scale, Insomnia Severity Scale, Patient Health Questionnaire-9 (PHQ-9), Pittsburgh sleep quality index and Berlin Questionnaire.
Results
Participants with RLS symptoms had a higher prevalence of depression, defined by a PHQ-9 score ≥ 10 (OR 3.03, CI 1.11–8.26) and eveningness in chronotype (odds ratio 1.95 confidence interval 1.15–6.43) when adjusted for depression, excessive daytime sleepiness, insomnia symptom and morningness-eveningness. However, RLS symptoms had no association with excessive daytime sleepiness and insomnia, when adjusted for clinical factors.
Conclusions
In Korean high school students, restless leg symptom may be preceded by depression and eveningness of chronotype. For healthy sleep lifestyle in the adolescents, an appropriate evaluation of RLS symptom as well as chronotype is recommended. Original ArticleFri, 02 Dec 2016 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=83Effects of Melatonin-Rich Milk on Mild Insomnia Symptomshttp://www.sleepmedres.org/journal/view.php?number=84
Background and Objective
Insomnia symptoms are common in the general population. This study evaluated the effects of melatonin-rich milk, which contains 10 times more melatonin than usual milk, on insomnia symptoms.
Methods
Double-blind randomized placebo-controlled trial was performed. A total of 91 subjects aged 21−69 years with mild insomnia symptoms were recruited from the community. All the subjects underwent baseline studies for insomnia severity index, Pittsburgh sleep questionnaire index, Epworth sleepiness scale (ESS), Beck depression inventory and a sleep satisfaction scale (range 1−10). For two weeks, the subjects consumed a cup of either melatonin-rich milk or usual milk before going to sleep. Two weeks later, they completed the same questionnaires used in the baseline. Changes in the questionnaire scores for each group were calculated, after which we compared the differences between the two groups.
Results
Among 91 subjects (male 18, female 73, age 42.1 ± 14.1 years), 44 subjects drank the melatonin-rich milk and 47 drank the usual milk. There was no statistical difference in demographic variables between the two groups. Subjects consuming the melatonin-rich milk reported an improvement in sleep satisfaction scale than the usual milk group (p = 0.023), with significant improvement observed in the subjects aged 20−30 years (p = 0.048). In the ESS Scale, the subjects who had daytime sleepiness showed significant improvement difference between the two groups (p = 0.014), especially in the 20−30 years age group (p = 0.031).
Conclusions
Melatonin-rich milk could be an easy and beneficial regimen for young people suffering from mild insomnia, by preventing the development of chronic insomnia.Original ArticleThu, 15 Dec 2016 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=84Reliability of Manual and Automatic Scoring of Single Channel Nasal Airflow Device (ApneaLink) ...http://www.sleepmedres.org/journal/view.php?number=86
Background and Objective
ApneaLink (AL) is a single-channel portable monitoring device that identifies apnea or hypopnea from nasal airflow and is commonly used for screening and diagnosis of obstructive sleep apnea (OSA). This study aimed to evaluate the reliability of automatic and manual scoring of AL in patients with moderate or severe OSA.
Methods
This was a retrospective single-center study. Consecutive patients who underwent AL and confirmatory standard polysomnography (PSG) for evaluation of OSA within a 3-month interval were included. Sensitivity, specificity and receiver operating characteristic curves for AL were calculated for automatic and manual scoring with the apnea-hypopnea index (AHI). Pearson correlations and Bland- Altman plots were computed.
Results
Eighty-one patients were included. Overall, their mean age was 56 ± 10 years, and 80% were male. A correlation was found between the AL and PSG AHI and the apnea index but not with the hypopnea index. AL showed high sensitivity (82.7%) for moderate OSA with a good area under the curve (AUC) value of 0.710. Compared with automatic scoring methods, manual scoring provided higher AUC and specificity as well as positive and negative predictive value.
Conclusions
This study shows a high level of agreement in the AHI between AL and PSG performed within 3 months. The result of manual scoring with AL was more in agreement with overnight PSG than the result of automatic scoring was.<BR><p align='center'><img src='/upload/thumbnails/smr-main--2-68-.jpg' border=0></p>Original ArticleSat, 31 Dec 2016 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=86Narcolepsy Patient Presenting as Drop Attack without Emotional Triggering and Subjective Sleepinesshttp://www.sleepmedres.org/journal/view.php?number=85
Narcolepsy type I is characterized by excessive daytime sleepiness (EDS), cataplexy, sleep paralysis, hypnagogic hallucination, and fragmented night-time sleep. Although diagnosis is based on clinical history, it needs to be confirmed by nocturnal polysomnography, followed by a daytime multiple sleep latency test (MSLT). However, EDS, which is the central symptom of the narcolepsy, is unspecific and there could be a disparity between subjective daytime sleepiness and objective daytime sleepiness measured by MSLT. Also, cataplexy, which is the exclusive symptom of narcolepsy, has a wide phenotypical variability and is triggered by a range of stimuli, even without definite identifiable emotional trigger. We report an unusual narcolepsy patient with spontaneous cataplexy, without an identifiable trigger and subjective daytime sleepiness.Brief CommunicationThu, 15 Dec 2016 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=85Environmental Noise and Sleep Disturbance: Night-to-Night Variability of Sleep/Wake Patternhttp://www.sleepmedres.org/journal/view.php?number=87
Actigraphy is useful to assess sleep pattern of subjects for several days to several weeks, and collected sleep data is usually averaged out to know the general sleep pattern of each individual. However, intra-individual variability should be considered when assessing sleep patterns, with regard to the phenomenon of daily fluctuation. The aim of this study was to explore whether the mean sleep indices reflect intra-individual variability with regard to environmental noise. Indoor noise and sleep pattern were collected over 5 days, among 22 citizens of Ulsan Metropolitan city. We observed an association between environmental noise indices and various sleep indices such as sleep efficiency, number of awakenings, or fragmentation indices when we analyzed the data of 108 nights from 22 subjects. However, the significances were weakened when we analyzed noise and sleep/wake pattern after averaging out. In conclusion, we observed that the sleep/wake pattern over several days to weeks should not be averaged out when studied in relation with variable physiological phenomena, such as night-to-night variability.Brief CommunicationSat, 31 Dec 2016 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=87Sleep and Alzheimer’s Diseasehttp://www.sleepmedres.org/journal/view.php?number=62
<p>Sleep architecture and sleep patterns normally change with aging. In preclinical Alzheimer’s disease (AD), the accumulation of amyloid plaques begins 10 to 20 years before any cognitive symptoms progress. Soluble amyloid-β (Aβ) is secreted during physiological synaptic activity. Since synaptic activity is correlated with sleep and awake state, a degree of Aβ fluctuates in a diurnal sleep pattern. In animal and human studies, a degree of sleep quality showed a significant correlation with brain levels of Aβ and a risk of AD. Conversely, Aβ aggregation would debilitate neuronal function in brain regions critical to sleep and wake promotion. This bidirectional relationship can be explained as positive feedback loop and associated factors that influence this relationship. In AD, the degree of sleep disturbances is much more severe compared with in the normal elderly. Further, Sundowning syndrome and a reduction of melatonin level cause a stressful neuropsychiatric symptoms and a disruption of physiological sleep rhythm, respectively. In AD patients, a correlation between sleep architectural modifications and learning performances has been reported. Moreover, executive function and emotional reactivity might be attenuated by sleep disturbances, too. However, sleep disturbance does not impact cognitive functions of all patients with AD. This could support an individual and potentially genetically determined susceptibility. Sleep disturbances have an important effect on patients and caregivers. It has a critical value to confirm and treat individuals with sleep disorders and to explore whether good quality of sleep in humans can decrease the progression of preclinical to symptomatic AD.</p><BR><p align='center'><img src='/upload/thumbnails/smr-main--1-1-.jpg' border=0></p>Review ArticleTue, 30 Jun 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=62Cognitive Behavioral Therapy for Insomnia: Is it Effective in Treating Symptoms of Comorbid ...http://www.sleepmedres.org/journal/view.php?number=58
<p>Insomnia is a highly comorbid disorder with other psychiatric and physical illnesses. Cognitive behavioral therapy for insomnia (CBTI) is effective for treating insomnia symptoms. Additionally, it is also effective in treating symptoms of the comorbid psychiatric and physical illnesses, and is recommended as an adjunctive treatment to enhance treatment effects of the original disorder. This current article is a review of CBTI with comorbid physical and psychiatric disorders.</p>Review ArticleTue, 30 Jun 2015 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=58Subjective Sleep Disturbance in People with Epilepsy: Prevalence and Impact on Health-Related ...http://www.sleepmedres.org/journal/view.php?number=59
<sec>
<title>Background and Objective</title>
<p>It is not well known whether sleep disturbances affect quality of life (QoL) independent of mood disturbance in people with epilepsy. The aim of this study was to investigate the prevalence of sleep disturbances and the impact on QoL in people with epilepsy.</p></sec>
<sec>
<title>Methods</title>
<p>This was a cross-sectional study involving adults with epilepsy and controls. Sleep disturbances, depression, anxiety, and QoL were assessed using several questionnaires. The direct effect of sleep disturbance on QoL was assessed using multiple linear regression analysis, and a mediational model designed with the assumption that sleep disturbances affect QoL through a mediator was tested.</p></sec>
<sec>
<title>Results</title>
<p>A total of 168 people with epilepsy and 56 controls were enrolled. Difficulty maintaining sleep (16.1%) and waking up too early in the morning (13.1%) were more common in patients than controls (p &lt; 0.05). There were no differences in daytime sleepiness, sleep apnea, and restless legs syndrome between the groups. Patients had more sleep problems in the Medical Outcomes Study-Sleep Scale than controls. The effect of sleep disturbance on Quality of Life in Epilepsy 10 (QOLIE-10) lost its statistical significance (β = −0.021, p = 0.769) after controlling for Hospital Anxiety and Depression Scale (HADS). The Sobel test confirmed that the effect of sleep disturbance on QOLIE-10 was significantly mediated by both HADS-depression (β = −0.195, p &lt; 0.001) and HADS-anxiety (β = −0.265, p &lt; 0.001).</p></sec>
<sec>
<title>Conclusions</title>
<p>Sleep disturbances, especially insomnia, were more common in people with epilepsy. Although sleep disturbance seems to have no direct effects on QoL, it appears to have an indirect effect on QoL through depression and anxiety in people with epilepsy.</p></sec>Original ArticleTue, 30 Jun 2015 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=59Do Adenoids Regrow after Adenoidectomy?http://www.sleepmedres.org/journal/view.php?number=57
<sec>
<title>Background and Objective</title>
<p>To compare the correlation between nasopharyngeal airway 1 month and 1 year after adenoidectomy using skull lateral views and subjective symptoms.</p></sec>
<sec>
<title>Methods</title>
<p>Thirty two children who underwent adenoidectomy and tonsillectomy from January 2003 through June 2006 were included. All were checked by skull lateral view as described above by retrospective review of medical records. Measurements included the nasopharyngeal air space from the choana to the lowest margin of C1 and the narrowest diameters of the nasopharyngeal air space and adenoid area. The adenoid-nasopharyngeal air space was determined as the A/N ratio. The parents completed a visual analog scale questionnaire at 1 month and 1 year post-operatively.</p></sec>
<sec>
<title>Results</title>
<p>The adenoidal-nasopharyngeal ratio was significantly increased at post-operative 1 year compared to 1 month after adenoidectomy on skull lateral views (p = 0.024). There was no significance of the size change between the other parameters in the 1 month and 1 year post-operative skull lateral views. There was no significant correlation between all parameters in the 1 month and 1 year post-operative skull lateral views, and change of subjectively rated symptoms.</p></sec>
<sec>
<title>Conclusions</title>
<p>There was no significant correlation between adenoid regrowth after adenoidectomy and the change of subjective symptoms.</p></sec>Original ArticleTue, 30 Jun 2015 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=57Relationships between Nocturia, Obstructive Sleep Apnea, and Quality of Sleephttp://www.sleepmedres.org/journal/view.php?number=60
<sec>
<title>Background and Objective</title>
<p>Nocturia is one of the common causes of sleep disturbance in adults, often associated with obstructive sleep apnea (OSA). The purpose of this study was to investigate the association between nocturia and OSA, and their effects on quality of sleep in adults.</p></sec>
<sec>
<title>Methods</title>
<p>This study included 107 patients who visited the urology outpatient due to lower urinary tract symptoms with or without sleep-related symptoms, assessed by using either the International Prostate Symptom Score in men or the Overactive Bladder symptoms in women. Based on these questionnaires, subjects were divided into nocturia and nocturia-free groups. In addition, all subjects completed detailed sleep questionnaires including the Global Sleep Assessment Questionnaire (GSAQ) and the Berlin Questionnaire (BQ), and provided details of voiding volumes and times. Night polysomnography (PSG) was performed in subjects with high risk of OSA, as indicated by the BQ.</p></sec>
<sec>
<title>Results</title>
<p>Among the 107 study subjects (43 males, 64 females, mean age 59.2 ± 11.2 years), nocturia was present in 54.2% (58/107), self-reported sleep disturbance in 26.2% (28/107), and a high risk of OSA, with BQ &gt; 10 points, was present in 29.0% (31/107) of subjects. The nocturia group had a significantly higher mean GSAQ total score than the nocturia-free group, indicating poorer sleep quality (p = 0.004). Nocturia was more frequent in patients with moderate or severe OSA than in patients with mild OSA (p = 0.006) based on PSG.</p></sec>
<sec>
<title>Conclusions</title>
<p>Nocturia was a clinically significant sleep disturbing factor, and it was more frequent in patients with more severe OSA.</p></sec><BR><p align='center'><img src='/upload/thumbnails/smr-main--1-28-.jpg' border=0></p>Original ArticleTue, 30 Jun 2015 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=60Treatment of Obstructive Sleep Apnea Using Temporary Mandible Advancement Device: A Case Reporthttp://www.sleepmedres.org/journal/view.php?number=61
<p>Obstructive sleep apnea (OSA) is the most prevalent type of sleep apnea, and oral appliance may be one of the options for treatment of OSA. But, the problems with the oral appliance are high cost, possible low compliance, and complications such as temporomandibular disorder. In this article, we described a severe OSA case that was successfully improved by using temporary mandible advancement device, which was designed for therapeutic effect of mandible advancement with low cost and simplified fabrication procedure.</p>Brief CommunicationTue, 30 Jun 2015 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=61Four Narcolepsy Cases after H1N1 Infection or Vaccinationhttp://www.sleepmedres.org/journal/view.php?number=63
<p>This report describes 4 narcolepsy cases that were developed after Influenza A/H1N1 infection or vaccination. The durations from Influenza A/H1N1 infection or vaccination to the symptom onset were 10 days, 2 weeks, 3 months, 6 months respectively. Among the four, two were teenagers or younger. One of them developed symptoms after Influenza A/H1N1 infection while three of them developed after vaccination. All went through polysomnography followed by multiple sleep latency tests for accurate diagnosis. All suffered from cataplexy. However, one of them presented with negative results in the human leukocyte antigen DQB1*0602 study. These cases suggest a possibility an association between H1N1/Influenza A virus and narcolepsy development via immune mechanism.</p>Brief CommunicationTue, 30 Jun 2015 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=63High Flow Nasal Cannula Therapy for Improving Obstructive Sleep Apnea: A Case Reporthttp://www.sleepmedres.org/journal/view.php?number=64
<p>Although continuous positive airway pressure is the treatment of choice for obstructive sleep apnea, its compliance is low. Therefore, alternative therapeutic strategies are often required. High flow nasal cannula therapy uses an air compressor to deliver a constant flow of oxygen via the nasal cannula at a maximum of 60 L/m. It can produce positive end expiratory pressure and increase end expiratory pharyngeal pressure, which can help to alleviate upper airway obstruction. This is a case report of high flow nasal cannula therapy for a 71 year-old man. He had an obstructive sleep apnea and severe desaturation but failed to use continuous positive airway pressure. He underwent titration with high flow nasal cannula under polysomnography. Using high flow nasal cannula at an airflow of 45 L/m, his apnea-hypopnea, respiratory arousal and oxygen desaturation were improved. Importantly, he is very compliant with high flow nasal cannula therapy.</p>Brief CommunicationTue, 30 Jun 2015 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=64Sleep Disturbances in Cancer: A Reviewhttp://www.sleepmedres.org/journal/view.php?number=65
<p>Sleep problems are one of the major complaints in patients with cancer, before treatment, while undergoing chemotherapy or radiation therapy, and after the completion of cancer treatment. As in other medically ill patients, disturbed sleep in cancer patients may be an important contributor to poor quality of life, to their tolerance to treatment, and to the development of mood disorders, particularly depression. Disruptions in circadian rhythms also affect sleep. The degree of sleep disruption found in patients with cancer is not trivial. Objectively recorded sleep and biological rhythms confirm that these are major problems in cancer patients.</p>Review ArticleTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=65Structural Brain Neuroimaging in Primary Insomniahttp://www.sleepmedres.org/journal/view.php?number=66
<p>Primary insomnia is a chronic disorder and characterized by inadequate sleep or poor sleep quality. The prevalence of insomnia is relatively high and daytime fatigue, mood disruption and cognitive impairments associated with insomnia negatively affect productivity and quality of life of patients. However, the neurobiological understanding of primary insomnia is still insufficient. Meanwhile, many neuroimaging studies have performed to investigate the structural or functional derangement in brains of patients with primary insomnia. There is no doubt that neuroimaging techniques can be useful in identifying the cerebral mechanisms of insomnia pathogenesis, and the neural correlates of insomnia symptoms. The current review focuses on structural neuroimaging findings in patients with primary insomnia.</p>Review ArticleTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=66Nasal Mass Presenting as Obstructive Sleep Apnea Syndromehttp://www.sleepmedres.org/journal/view.php?number=67
<sec>
<title>Background and Objective</title>
<p>The aim of this study was to analyze the clinical symptoms, physical examinations, imaging studies, polysomnographic evaluations, and pathologic findings of patients with a nasal mass presenting as obstructive sleep apnea syndrome (OSAS).</p></sec>
<sec>
<title>Methods</title>
<p>The study population consisted of adult OSAS patients who had a nasal mass and were successfully treated by nasal surgery alone. In this study, we analyzed clinical symptoms, physical examinations, imaging studies, pre and postoperative polysomnographic parameters, and pathologic results of these patients.</p></sec>
<sec>
<title>Results</title>
<p>A series of four patients with OSAS due to a nasal mass were analyzed. The analysis revealed the following: 1) A nasal mass involving the nasopharyngeal space may cause mild to severe OSAS. 2) Isolated nasal surgery may be efficient for the improvement of respiratory disturbances in an OSAS patient with a large nasal mass. 3) We speculated that favorable indications for isolated nasal surgery for the treatment of OSAS are as follows: (1) a huge nasal mass occupying the nasopharynx, (2) small tonsils, (3) low-leveled tongue, (4) relatively young age, and (5) the absence of morbid obesity.</p></sec>
<sec>
<title>Conclusions</title>
<p>Nasal masses should be considered surgically correctable anatomical abnormalities and potential causes of obstruction when assessing patients with suspected OSAS.</p></sec><BR><p align='center'><img src='/upload/thumbnails/smr-main--2-54-.gif' border=0></p>Original ArticleTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=67Association of PER2 and CRY1 Polymorphisms with the Morningness-Eveningness in Korean Adultshttp://www.sleepmedres.org/journal/view.php?number=68
<sec>
<title>Background and Objective</title>
<p>Individuals have a unique circadian preference, which is based on differences in endogenous rhythm and environmental factors. There has been no study on the relationship between the morningness-eveningness (ME) preference and the polymorphisms of PER2 and CRY1 genes, which may play an essential role in the modulation of circadian rhythm. Our present study aims to examine the difference in the polymorphisms of PER2-2221A/G and CRY1-2790T/G, which are related to a greater cancer risk, according to the ME preference.</p></sec>
<sec>
<title>Methods</title>
<p>The Korean version of the Morningness-Eveningness Questionnaire was administered and buccal DNA samples were obtained from 425 Korean adults aged 18 years or older. We excluded subjects who were being treated for sleep disorders or those with shift work. 47 morning type (MT) (age: 44.57 ± 12.33, M:F = 14:33) subjects, 59 neither type (NT) (age: 35.20 ± 9.53, M:F = 20:39) subjects and 51 evening type (ET) (age: 28.80 ± 8.03, M:F = 14:37) subjects were finally included in the present study. The above candidate single nucleotide polymorphisms were analyzed by DNA sequencing or a SNaPshot assay.</p></sec>
<sec>
<title>Results</title>
<p>For the PER2-2221A/G and CRY1-2790T/G, there were no significant differences in the genotype distribution, allele frequency, or proportion of G allele positive subjects between the MT and ET groups. There was no significant difference in the mean scores of the MEQ-K, KESS, or PSQI between G allele positive and negative subjects for either PER2-A2221A/G or CRY1-2790T/G.</p></sec>
<sec>
<title>Conclusions</title>
<p>Our study did not support the association of the ME preference with the PER2-2221 A/G and CRY1-2790T/G in Korean adults.</p></sec>Original ArticleTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=68The Use of Mobile Applications to Monitor Sleep Quality and Alertness during Shift Work in ...http://www.sleepmedres.org/journal/view.php?number=69
<sec>
<title>Background and Objective</title>
<p>Fatigue or inattentiveness in nurses during shift work affects patient safety. Therefore, sleep quality and alertness during shift work requires monitoring. The aims of this study were to: 1) compare sleep parameters measured using sleep logs and mobile sleep applications and 2) evaluate sleep quality and alertness during shift work using mobile applications.</p></sec>
<sec>
<title>Methods</title>
<p>Twenty shift-work nurses voluntarily enrolled in the study. We compared sleep parameters including time in bed (TIB), sleep latency (SL), total sleep time, and wakefulness after sleep onset, recorded using sleep logs and mobile applications. An additional 66 female shift-work nurses voluntarily evaluated their sleep quality and alertness at work using the ‘Sleep Time’ and ‘Math Quiz’ applications.</p></sec>
<sec>
<title>Results</title>
<p>TIB was significantly lower in night-shift nurses (328.3 ± 8.9) than in nurses working other shifts (395.3 ± 9.1 min; p < 0.05). SL was significantly lower after a night shift (26.1 ± 1.7 min; p < 0.05) than after a day shift (31.5 ± 1.9 min) or a day off (31.0 ± 1.4 min). The Math Quiz scores did not vary by shift type, but sleepiness scores were significantly higher immediately after waking up (5.57 ± 0.15) and during work (4.91 ± 0.14) in night-shift nurses, as compared to other nurses (p < 0.05).</p></sec>
<sec>
<title>Conclusions</title>
<p>Mobile applications and sleep logs were both effective in measuring sleep parameters. Most shift-work nurses, particularly those working nights, slept poorly. Mobile sleep and arithmetical applications are objective, reliable, and feasible means of monitoring the sleep quality and alertness of shift-work nurses.</p></sec><BR><p align='center'><img src='/upload/thumbnails/smr-main--2-66-.gif' border=0></p>Original ArticleTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=69Same Pattern of Circadian Variation According to the Season in the Timing of Ischemic Stroke ...http://www.sleepmedres.org/journal/view.php?number=73
<sec><title>Background and Objective</title>
<p>Stroke occurrence shows a chronobiological variation, which is considered to be related with waking in the morning. We hypothesized that its seasonal difference would also exist because individual life activity including sleep-wake pattern can be influenced by interseasonal variability. The objective of this study was to investigate the seasonal difference of circadian variation in the timing of onset in patients with acute ischemic stroke.</p></sec>
<sec><title>Methods</title>
<p>We studied 1486 patients with acute ischemic stroke. Stroke onset time was defined as the earliest time the patient or a witness noted definite neurological symptoms. The patients with clear onset stroke were enrolled. Frequency of onset was analyzed for four 6-hour and twelve 2-hour intervals from 0 to 24 hour per day.</p></sec>
<sec><title>Results</title>
<p>The clear onset time was known in 968 patients (65.1%). Mean age of the patients was 67.63 ± 12.65 years and 589 patients (60.9%) were male. Stroke occurred in spring (26.5%), summer (27.2%), fall (24.1%), and winter (22.3%). In all cases, ischemic stroke showed a significant circadian variation in time of onset (p < 0.001). High peak period was between 6:01 AM to 12:00 PM (37%) with the same pattern in each season.</p></sec>
<sec><title>Conclusions</title>
<p>Seasonal difference was not significant despite circadian variation in time of onset of ischemic stroke. Thus, exogenous factors such as environmental factors and life styles may have less influence on inter-seasonal variability of circadian rhythms, which are related with chronobiological factors of stroke onset in this regional population.</p></sec>Original ArticleTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=73Severe Central Sleep Apnea/Hypopnea Syndrome Mimicking Rapid Eye Movement Sleep Behavior Disorderhttp://www.sleepmedres.org/journal/view.php?number=70
<p>Rapid eye movement sleep behavior disorder (RBD) is a sleep disorder characterized by loss of muscle atonia during rapid eye movement (REM) sleep associated with dream enactment. However, these complex behaviors can also occur in other sleep disorders, a clinical situation termed as “pseudo-RBD”. Anecdotal reports of obstructive sleep apnea syndrome simulating the clinical features of RBD have been reported. It has been suggested that “pseudo-RBD” is a form of a confusional arousal caused by a combination of severe oxyhemoglobin desaturations and other unknown factors. However, there have been no previous reports of RBD-like behaviors associated with central sleep apnea. Here, we describe two patients who reported complex motor and vocal behavior mimicking RBD, but REM sleep without atonia was not observed in video-polysomnography (VPSG). Furthermore, VPSG demonstrated severe central sleep apnea-hypopnea inducing abnormal motor and vocal behaviors.</p><BR><p align='center'><img src='/upload/thumbnails/smr-main--2-72-.gif' border=0></p>Brief CommunicationTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=70Post-Traumatic Narcolepsy Associated with Thalamic/Hypothalamic Injuryhttp://www.sleepmedres.org/journal/view.php?number=71
<p>The hypothalamus is an important structure that regulates sleep via hypocretin neurotransmission. Central nervous system disorders such as tumors and vascular legions involving the hypothalamus can cause secondary narcolepsy. In addition, brain trauma can contribute to post-traumatic narcolepsy despite lack of any definite brain lesion. Here, we present a case of a 37-year-old man suffering from a hypothalamus-to-thalamus hemorrhage after a traffic accident. After this trauma, he suffered from excessive daytime sleepiness and was diagnosed with post-traumatic narcolepsy by polysomnography and multiple sleep latency tests. He was positive for human leukocyte antigen (HLA)-DQB1*03:01 and HLA-DQB1*06:01 antigens.</p><BR><p align='center'><img src='/upload/thumbnails/smr-main--2-76-.gif' border=0></p>Brief CommunicationTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=71Restless Leg Syndrome Induced by an Acute Withdrawal of Oxycodonehttp://www.sleepmedres.org/journal/view.php?number=72
<p>Restless leg syndrome (RLS) can develop secondary to various medical conditions. Some medications, as well as some opioid withdrawal, are known to induce RLS. Opioids modulate the dopamine system via their receptors and change the sensitivity to dopamine. Abrupt withdrawal of opioid may cause an endogenous opioid deficit state and disturb the dopamine system, which can lead to a transient dopamine dysfunctional state such as RLS. We reported a man with secondary RLS after acute withdrawal of the opioid, oxycodone, which has not been previously reported.</p>Brief CommunicationTue, 01 Dec 2015 00:00:01 +0100http://www.sleepmedres.org/journal/view.php?number=72Role of Nose in Sleep-Disordered Breathinghttp://www.sleepmedres.org/journal/view.php?number=47
<p>The detailed pathophysiology and mechanisms of sleep-disordered breathing are not completely understood and the role of nose in sleep and obstructive sleep apnea has been still controversial. Considering that nasal obstruction has effects on anatomical factor, neuromuscular factor, and respiratory factor, nose may modulate upper airway collapsibility through anatomical, neuromuscular, and respiratory factors and play an important role of the pathogenesis of obstructive sleep apnea.</p>Review ArticleMon, 30 Jun 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=47The Effects of a Forest Kindergarten Program on the Sleep Habits of Preschool Childrenhttp://www.sleepmedres.org/journal/view.php?number=43
<sec>
<title>Background and Objective</title>
<p>It has been reported that preschool children attending a forest kindergarten had a more balanced development in the physical, emotional, and cognitive areas. We evaluated the effects of the forest kindergarten program on the sleep habits of preschool children.</p></sec>
<sec>
<title>Methods</title>
<p>Thirty-seven children (n = 18 in the forest kindergarten, n = 19 in a regular kindergarten) participated in this study. Parents of the children completed a Children’s Sleep Habits Questionnaire (CSHQ) at the initial assessment, and the CSHQ was repeated after 8 months of attending the kindergarten program.</p></sec>
<sec>
<title>Results</title>
<p>There were no significant differences between groups in terms of the CSHQ total and subscale measures at the initial assessment. After 8 months enrollment in a kindergarten program, the CSHQ total score (p &lt; 0.01), the subscale scores of sleep disordered breathing (p = 0.04), and daytime sleepiness (p &lt; 0.01) were significantly lower in children attending the forest kindergarten compared with those at the regular kindergarten. Within the forest kindergarten group, the total CSHQ score (p = 0.02) and the daytime sleepiness subscale score (p = 0.02) significantly decreased after 8 months in the program.</p></sec>
<sec>
<title>Conclusions</title>
<p>Preschool children who are educated in forest kindergarten programs had less problematic sleep habits and daytime sleepiness compared with children in the regular kindergarten program. Forest kindergarten programs may positively influence daytime sleepiness in children.</p></sec>Original ArticleMon, 30 Jun 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=43Comparison of Cognitive Function between Patients with Restless Legs Syndrome and Healthy Controlshttp://www.sleepmedres.org/journal/view.php?number=46
<sec>
<title>Background and Objective</title>
<p>Studies regarding cognitive function in patients with restless legs syndrome (RLS) show inconsistent results, although comorbid psychiatric conditions including depression and anxiety are common in these patients. We compared cognitive performance and depression symptoms between drug-naïve RLS patients and healthy controls, in order to determine whether the depression symptoms that result from RLS affect cognitive function.</p></sec>
<sec>
<title>Methods</title>
<p>Drug-naïve RLS patients (n = 15) and age-matched controls (n = 17) were enrolled in the study. They completed clinical interviews, sleep questionnaires, and a neuropsychological assessment battery that measured multiple cognitive domains including attention, language ability, memory, and executive function. Depression was measured using the Beck Depression Inventory-II. Statistical analyses included chi-square and non-parametric Mann-Whitney U tests, and Spearman correlations.</p></sec>
<sec>
<title>Results</title>
<p>Restless legs syndrome patients performed better than controls on tests of verbal memory and category word fluency (animal) (p &lt; 0.05). The RLS group had significantly higher depression scores than controls (p = 0.005). Depression scores for the RLS patients showed significant correlations with restless legs symptoms and several measures of sleep quality. There were no significant differences in cognitive function between patients with moderate to severe depression (n = 6) and those without depression (n = 6).</p></sec>
<sec>
<title>Conclusions</title>
<p>Our study did not confirm that symptoms of RLS were associated with cognitive dysfunction. In addition, depression symptoms had little impact on cognitive function, but were independently associated with symptoms of RLS regardless of cognitive function.</p></sec>Original ArticleMon, 30 Jun 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=46Clinical Efficacy of Symptomatic Manifestations in Prediction of Pediatric Obstructive Sleep Apneahttp://www.sleepmedres.org/journal/view.php?number=45
<sec>
<title>Background and Objective</title>
<p>This study was aimed to identify clinical efficacy of subjective symptoms in prediction of obstructive sleep apnea (OSA) in children.</p></sec>
<sec>
<title>Methods</title>
<p>Medical records of children under age of 12 years who underwent attended full night polysomnography were reviewed. Questionnaires in the Korean version of OSA-18 were answered by all of the patients. Among the questionnaires, the scores of snoring, apnea and mouth breathing were summated to analyze the correlation between subjective symptoms and apnea hypopnea index (AHI). The hypertrophy of the tonsils and adenoids were graded from 1 to 4.</p></sec>
<sec>
<title>Results</title>
<p>A total of 68 patients (45 males and 23 females) were included in this study. The average age of patients was 6.9 years. The average score of snoring, apnea and mouth breathing was 5.1, 3.7 and 5.1, respectively. The average grade of tonsil and adenoid hypertrophy was 2.9 and 2.5, respectively. While the Korean version of OSA-18 score and AHI did not show a significant correlation (p = 0.222), the sum of snoring, apnea and mouth breathing score showed a significant correlation with AHI (p = 0.019). A composite score including snoring, apnea, mouth breathing, and adenotonsillar hypertrophy was also correlated with AHI (p = 0.035). However, adenotonsillar hypertrophy was not correlated with AHI.</p></sec>
<sec>
<title>Conclusions</title>
<p>The present study showed that OSA in children was better predicted by subjective symptoms, in particular, snoring, apnea and mouth breathing than adenotonsillar hypertrophy.</p></sec>Original ArticleMon, 30 Jun 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=45Home Sleeping Conditions and Sleep Quality in Low-Income Preschool Childrenhttp://www.sleepmedres.org/journal/view.php?number=48
<p>We investigated associations between the home sleeping conditions and sleep quality of low-income preschool children. Parents of pre-school children in Head Start programs in Michigan in the United States completed a sleep environment survey, which asked parents about their children’s sleep conditions. They also completed the Children’s Sleep Habits Questionnaire, on which higher scores reflect worse quality sleep. Among 120 preschoolers, 52% shared a bed and 53% shared a room at least once per week. Poor sleep quality was correlated with the frequency of sharing a room with parents, falling asleep with the TV on, sleeping in a place that was too bright, and inversely with sleeping alone in one’s own bed. Stepwise regression analysis revealed sleeping alone in his/her own bed was associated with better sleep quality (β = −0.24, standard error = 0.47, p = 0.01). We found that bed-sharing is associated with poorer sleep quality in low-income families.</p>Brief CommunicationMon, 30 Jun 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=48Orthodontic Treatment with Rapid Maxillary Expansion for Treating a Boy with Severe Obstructive ...http://www.sleepmedres.org/journal/view.php?number=44
<p>This case report shows that orthodontic treatment with rapid maxillary expansion (RME) is an effective treatment option for managing pediatric obstructive sleep apnea (OSA). An 11-year-old boy with severe pediatric OSA received comprehensive orthodontic treatment with RME. Four sleep studies were done: before orthodontic treatment, after RME, just after comprehensive orthodontic treatment and at the 2-year and 5-month follow-up. Polysomnographic findings showed that the orthodontic treatment with RME was successful for managing severe OSA in the patient.</p>Brief CommunicationMon, 30 Jun 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=44Cultural Issues of Co-Sleeping in Koreahttp://www.sleepmedres.org/journal/view.php?number=50
<p>Co-sleeping is a natural part of parenting in the Eastern culture; however, it may seem strange and possibly even dangerous to Western cultures. In the West, parental age, race, marital status, and house income may influence co-sleeping, while co-sleeping, especially bed-sharing, is usually considered to increase the risk of sudden infant death syndrome. In Korea, however, people usually believe that a baby must not sleep alone in an empty room. The differences in the prevalence of co-sleeping between Eastern and Western society may be rooted in differences in child-care philosophies, sleeping habits, and home architecture. In this article, the hazards and benefits of bed-sharing will be reviewed, and differences in co-sleeping will be addressed from a cultural viewpoint.</p>Review ArticleTue, 30 Dec 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=50Aberrant Gray Matter Structure Associated with Sleep Disturbance in the Drug Naïve Subjects ...http://www.sleepmedres.org/journal/view.php?number=51
<sec>
<title>Background and Objective</title>
<p>Although the sleep disturbances are very common and serious behavioral symptoms in Alzheimer’s disease (AD), the neuronal substrate of the gray matter structures associated with sleep disturbances in AD were not clear. The aim of this study is to investigate distinctive correlation patterns between the gray matter volume and sleep disturbances in AD.</p></sec>
<sec>
<title>Methods</title>
<p>Thirty drug-naïve patients with AD and 30 group-matched healthy control subjects underwent 3T magnetic resonance imaging scanning, and the whole brain gray matter volumes were measured using voxel based morphometry. We explored the correlation pattern between the gray matter volumes and the sleep disturbances in AD using the sleep disturbance subscale of Neuropsychiatric Inventory (NPI).</p></sec>
<sec>
<title>Results</title>
<p>Significant negative correlations were observed between left dorsolateral prefrontal cortex (DLPFC) and hypothalamus volumes and sleep disturbance subscale of NPI (false discovery rate corrected for multiple comparisons p &lt; 0.05).</p></sec>
<sec>
<title>Conclusions</title>
<p>This study was the first to explore the relationships between whole brain gray matter volumes and sleep disturbances of drug-naïve patients with AD. These structural changes in DLPFC and hypothalamus might be the core of the underlying neurobiological mechanisms of sleep disturbances in AD.</p></sec>Original ArticleTue, 30 Dec 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=51Change of Obstruction Site by Modified Jaw Thrust Maneuver in Obstructive Sleep Apnea Patientshttp://www.sleepmedres.org/journal/view.php?number=52
<sec>
<title>Background and Objective</title>
<p>We evaluated possibility of modified jaw thrust maneuver with drug induced sleep endoscopy (DISE), as an indicator of mandibular advancement treatment such as mandibular advance device, geniohyoid advancement and other treatment modalities.</p></sec>
<sec>
<title>Methods</title>
<p>Sixty seven Korean male, obstructive sleep apnea patient, confirmed by full night polysomnography were enrolled. We performed DISE and analyzed obstruction sites before and after modified jaw thrust maneuver. Degree of improvement in obstruction more than one grade of obstruction, was defined as “responder by modified jaw thrust maneuver”. Non-responder was defined as the airway does not open by the modified jaw thrust maneuver. Association was analyzed among the patient’s characteristics [body mass index (BMI), Friedman stage, and respiratory disturbance index (RDI)] and the results.</p></sec>
<sec>
<title>Results</title>
<p>In retropalatal level obstruction, responder by modified jaw thrust maneuver was most commonly observed at antero-posterior (AP) obstruction (70.31%) while it was least observed at combined obstruction (66.67%). In retroglossal level obstruction, responder by modified jaw thrust maneuver was most commonly observed at AP obstruction (77.50%), while lateral obstruction was least observed (68.75%). Between group comparisons including, group of responder and group of non-responder of combined obstruction of retropalatal level and lateral obstruction of retroglossal level, revealed that there were no statistically significant differences in BMI, Friedman stage, and RDI (p &lt; 0.05).</p></sec>
<sec>
<title>Conclusions</title>
<p>Airway obstruction did not extend to the same pattern by modified jaw thrust maneuver. Modified jaw thrust maneuver under DISE is a useful diagnostic tool and predictor of therapeutic effects of mandibular advancement treatment.</p></sec>Original ArticleTue, 30 Dec 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=52Validity of Korean Version of Functional Outcomes of Sleep Questionnaire in Patients with ...http://www.sleepmedres.org/journal/view.php?number=49
<sec>
<title>Background and Objective</title>
<p>We developed a Korean version of the Functional Outcomes of Sleep Questionnaire (K-FOSQ) and investigated its reliability and validity in simple snorer or obstructive sleep apnea (OSA) patients.</p></sec>
<sec>
<title>Methods</title>
<p>A total 432 participants (70% men, 84% OSA, mean age 50.0 ± 9.8 years) who were simple snorers or had OSA were included. We assessed the internal consistency, test-retest reliability, factor analysis, multitrait scaling analysis, and the concurrent validity of the K-FOSQ. Participants completed a battery of questionnaires including the Epworth Sleepiness Scale (ESS), Short Form-36 Health Survey (SF-36), Medical Outcomes Study-Sleep (MOS-Sleep) Scale, and Beck Depression Inventory (BDI).</p></sec>
<sec>
<title>Results</title>
<p>Factor analysis identified five factors, in which only 24 items met the loading criteria. The five factors of K-FOSQ accounted for 73.0% of the variance. Cronbach’s alpha coefficient for all domains exceeded the 0.70 standard for internal consistency. Test-retest reliability was acceptable (r = 0.41–0.93). Item-domain correlations ranged from 0.37 to 0.90. Only one item did not reach the threshold of 0.40. Floor effects were not observed, but ceiling effects were marked on all K-FOSQ subscales except one. All domains of K-FOSQ were significantly correlated with the corresponding scores of all tested instruments. The global K-FOSQ had a strong correlations (r &gt; 0.50) with ESS and Sleep Problem Index-2 of MOS-Sleep, and had medium-sized correlations (r = 0.40–0.50) with BDI and SF-36 total scores. The K-FOSQ global and subscales did discriminate between participants with and without daytime sleepiness, but not between simple snorers and OSA patients.</p></sec>
<sec>
<title>Conclusions</title>
<p>The K-FOSQ is a reliable and valid instrument for assessing functional outcome in participants with daytime sleepiness.</p></sec>Original ArticleMon, 30 Jun 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=49Prevalence, Risk Factors, and Impact of Excessive Daytime Sleepiness in an Elderly Korean Populationhttp://www.sleepmedres.org/journal/view.php?number=54
<sec>
<title>Background and Objective</title>
<p>Excessive daytime sleepiness (EDS) is commonly reported by the elderly, but has not been well-described in older adults in Korea. This study aimed to estimate the prevalence and risk factors of EDS, and investigated the relationship between EDS and cognitive impairment in an older Korean population.</p></sec>
<sec>
<title>Methods</title>
<p>The cross-sectional and community-based study recruited 333 people ≥ 60 years of age. All participants underwent full-time nocturnal polysomnography and completed questionnaires assessing sociodemographic factors. EDS was defined as Epworth Sleepiness Scale score &gt; 10. Cognitive functions were estimated using the Korean version of the Consortium to Establish a Registry for Alzheimer’s Disease neuropsychological assessment battery and subjective memory complaint questionnaire.</p></sec>
<sec>
<title>Results</title>
<p>The overall prevalence of EDS was 18.9% with no significant difference between genders. In multivariate analysis using a multiple logistic regression model, obesity [odds ratio (OR) = 2.379, p = 0.022], educational attainment (OR = 0.929, p = 0.019) and total arousal (OR = 2.785, p = 0.008) were identified as the risk factors for EDS. Subjective memory impairment was related to EDS after controlling for confounding variables (p &lt; 0.001).</p></sec>
<sec>
<title>Conclusions</title>
<p>Korean elderly have a high prevalence and risk factors of EDS, which has modest effects on cognitive functioning. EDS in older adults should be adequately addressed and treated, instead of being considered as a normal aging process.</p></sec>Original ArticleTue, 30 Dec 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=54Release Pattern of Salivary Chromogranin A in Pediatric Subjects with Obstructive Sleep Apneahttp://www.sleepmedres.org/journal/view.php?number=53
<sec>
<title>Background and Objective</title>
<p>Sleep-disordered breathing (SDB) is associated with activation of the stress response, including the autonomic nervous system. Salivary chromogranin A (sCgA) is considered a valuable indicator of sympathoadrenal activity. We examined the relationship between sCgA and polysomnography (PSG) parameters.</p></sec>
<sec>
<title>Methods</title>
<p>In this prospective study, we enrolled 103 children who underwent a physical examination and fully attended in-lab PSG. Saliva was collected at night before PSG and in the early morning after PSG.</p></sec>
<sec>
<title>Results</title>
<p>The subjects (n = 103) were divided into control [n = 41, apnea-hypopnea index (AHI) ≤ 1] and obstructive sleep apnea syndrome (OSAS; n = 62, AHI &gt; 1) groups. The OSAS group was subdivided into mild (1 &lt; AHI ≤ 5), moderate (5 &lt; AHI ≤ 10), and severe (10 &lt; AHI) groups. There was no significant difference in the sCgA parameters between the control and OSAS groups. No significant difference was observed in sCgA parameters between the control group and OSAS subgroups (mild, moderate, and severe). No circadian rhythm was detected in sCgA secretion, and no difference in sCgA concentrations was measured at the two time points.</p></sec>
<sec>
<title>Conclusions</title>
<p>Our findings suggest that sCgA secretion was not influenced by OSAS severity and no definitive circadian rhythm was detected in pediatric subjects. Further study is needed to establish whether there is a circadian rhythm in pediatric subjects.</p></sec>Original ArticleTue, 30 Dec 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=53The Presence of Periodic Limb Movement Disorder in a Patient with Diabetes Mellitus and Optic ...http://www.sleepmedres.org/journal/view.php?number=55
<p>Wolfram syndrome (WFS) is characterized by diabetes insipidus, diabetes mellitus, optic atrophy, and deafness (DIDMOAD), together known as DIDMOAD. This syndrome is a rare autosomal recessive neurodegenerative disorder and typically begins wtih insulin-dependent diabetes mellitus. Periodic limb movement disorder (PLMD) is characterized by periodic episodes of repetitive, highly stereotyped, limb movement during sleep, which results in disturbed sleep. Its pathophysiology is unclear. It is associated with many conditions, but we were unable to find a previous report regarding WFS accompanied by PLMD. We therefore report, for the first time, about a patient with WFS presenting with PLMD and discuss its pathomechanism with a literature review.</p>Brief CommunicationTue, 30 Dec 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=55Symptomatic Narcolepsy and Generalized Seizures Following Surgery for Rathke’s Cleft Cysthttp://www.sleepmedres.org/journal/view.php?number=56
<p>Symptomatic narcolepsy is a rare disorder caused by other underlying neurological disorders. One of the most frequent causes for symptomatic narcolepsy is brain tumors, usually in the region of the third ventricle and the diencephalon. Depending on clinical profile, the mass effect or surgical removal of space occupying lesions may play a definitive causative role in the occurrence of narcolepsy symptoms. We report a woman with symptomatic narcolepsy that developed 2 years after surgical removal of Rathke’s cleft cyst, which has never before been reported as a causative factor for symptomatic narcolepsy. In addition, myoclonic and/or generalized tonic-clonic seizures were associated with a left thalamic lesion generated by a complication of surgery.</p>Brief CommunicationTue, 30 Dec 2014 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=56Sleep and Women’s Healthhttp://www.sleepmedres.org/journal/view.php?number=40
<p>Sex differences in sleep begin at a very early age and women report poorer sleep quality and have higher risk for insomnia than do men. Sleep may be affected by variation in reproductive hormones, stress, depression, aging, life/role transitions, and other factors. The menstrual cycle is associated with changes in circadian rhythms and sleep architecture. Menstruating women (even without significant menstrual-related complaints) often report poorer sleep quality and greater sleep disturbance during the premenstrual week compared to other times of her menstrual cycle. In addition to these sleep disturbances, women with severe premenstrual syndrome often report more disturbing dreams, sleepiness, fatigue, decreased alertness and concentration during the premenstrual phase. Sleep disturbances are also commonly reported during pregnancy and increase in frequency and duration as the pregnancy progresses. The precipitous decline in hormones and unpredictable sleep patterns of the newborn contribute to and/or exacerbate poor sleep and daytime sleepiness during the early postpartum period. Insomnia is also among the most common health complaints that are reported by perimenopausal women. Women are particularly vulnerable to developing insomnia disorder during these times of reproductive hormonal change. In this review, we present a discussion on the most relevant and recent publications on sleep across the woman’s lifespan, including changes in sleep related to menstruation, pregnancy, postpartum, and the menopausal transition. Treatment for sleep disturbances and insomnia disorder and special considerations for treating women will also be discussed.</p>Review ArticleSun, 30 Jun 2013 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=40The Sleeping Habits of Preschool Children Are Related to Temperament, Behavior, and Social ...http://www.sleepmedres.org/journal/view.php?number=35
<sec>
<title>Background and Objective</title>
<p>Children’s sleep habits are important for their health and development. Here, we investigated the relationship between sleep habits, behavior, personality, and social responsiveness in children.</p></sec>
<sec>
<title>Methods</title>
<p>A total of 38 preschool children were assessed using the Korean Child Behavior Checklist (K-CBCL), Junior Temperament and Character Inventory (JTCI), Children’s Sleep Habit Questionnaire (CSHQ), and Social Responsiveness Scale (SRS).</p></sec>
<sec>
<title>Results</title>
<p>Harm avoidance according to JTCI was positively correlated with bedtime resistance (r = 0.34; p = 0.04) and sleep anxiety on the CSHQ (r = 0.43; p &lt; 0.01). Emotional lability on the K-CBCL was significantly associated with parasomnias (r = 0.38; p = 0.02), while lower social cognition and social communication scores on the SRS were associated with sleep anxiety (r = −0.34; p = 0.03) and parasomnias (r = −0.38; p = 0.01). Path analysis showed that among the JTCI subscales, both harm avoidance and persistence were significantly associated with social cognition.</p></sec>
<sec>
<title>Conclusions</title>
<p>Clinicians should pay particular attention to psychological components as potential contributors to sleep habits when managing sleep problems in preschool children.</p></sec>Original ArticleSun, 30 Jun 2013 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=35Prolonged Sleep-Onset Latency during Chronic Sleep Restriction in Micehttp://www.sleepmedres.org/journal/view.php?number=38
<sec>
<title>Background and Objective</title>
<p>Even though we know that sleep is important for maintaining normal cognitive and behavioral functions, it is still unclear whether sustained sleep restriction, which is prevalent in modern society, is adaptive or whether it leads to a functionally and physiologically deteriorated state. On the assumption that sleep-onset latency (SOL) and sleep pressure are inversely correlated, we hypothesized that an adaptation to chronic sleep restriction (CSR) might pay off cumulative sleep pressure and thus we investigated the influence of CSR by measuring SOL as a function of sleep restriction day.</p></sec>
<sec>
<title>Methods</title>
<p>Mice (n = 9) were sleep deprived for 18 h a day using periodically rotating wheels. This was followed by a 6 h period of sleep opportunity (SO) that started at the beginning of each light period. This sleep restriction protocol was repeated for 5 consecutive days. SOL was defined as the duration of wake state from light-on time to first non-rapid eye movement epoch. Total wake time during SO was calculated following sleep restriction and during the same period on baseline and during the first recovery day.</p></sec>
<sec>
<title>Results</title>
<p>SOL gradually increased from the first day of sleep restriction onward (paired t-test; p &lt; 0.01 for SR1 vs. SR5 and p &lt; 0.05 for SR3 vs. SR5). The linear regression slope of SOL as the function of SR days in individual mice showed a significantly positive drift (average R-squared = 0.69, average slope = 8.1 min/day).</p></sec>
<sec>
<title>Conclusions</title>
<p>In the present study, sleep onset was delayed in sleep restriction day compared to the baseline sleep and SOL increased across chronic sleep restriction days in mice. This finding is different from our expectation that SOL will decrease compared to baseline sleep and then return to baseline level as CSR continues. Instead, SOL increased gradually as a function of sleep restriction days. This indicates that SOL may not simply reflect sleep pressure, rejecting our assumed inverse correlation between SOL and sleep pressure.</p></sec>Original ArticleSun, 30 Jun 2013 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=38A Case of Frequent Arousal Following Nocturnal Dyspnea Caused by Gastroesophageal Reflux Diseasehttp://www.sleepmedres.org/journal/view.php?number=37
<p>Gastroesophageal reflux disease (GERD) is a common disorder that is associated with many esophageal syndromes and complications. Most cases of reflux event occur during the day, but reflux during sleep can cause not only esophageal problems, but also sleep problems, such as arousal and poor sleep quality. We report the case of a 17-year-old man who had been referred to us with frequent arousal following sudden dyspnea. On polysomnography, no respiratory disturbances and periodic limb movements were found during the sleep study, but frequent events of arousal were reported (arousal index: 12.3/h). On a 24-hr esophageal pH monitoring test, his DeMeester score was 176.43 and the total reflux time was 1120.9 min (76.9%), indicating the presence of significant acid reflux. After treatment with a proton-pump inhibitor, the arousals following nocturnal dyspnea and fatigue in the morning disappeared in the patient. GERD should be considered as a cause of spontaneous arousal or awakening not accompanying respiratory disturbances.</p>Brief CommunicationSun, 30 Jun 2013 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=37Overlap Syndromehttp://www.sleepmedres.org/journal/view.php?number=36
<p>Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) were common disorder that has been gaining increased attention as an important factor affecting health. The coexistence of COPD and OSA, which was termed overlap syndrome, is assumed to have affected many patients. The increases in morbidity or mortality are higher in patients with overlap syndrome than in patients with OSA or COPD alone. Nevertheless, the impact of OSA on COPD is not yet known. Patients with COPD experience sleep-related abnormalities, including sleep-disordered breathing associated with low sleep quality and hypoxia. Continuous positive airway pressure treatment accompanied by oxygen therapy has recently been attracting attention as the treatment of choice for overlap syndrome. Clinical consideration should be given to its potential sleep-related features that have not yet been recognized in order to improve clinical symptoms and quality of life for patients affected by overlap syndrome.</p>Review ArticleMon, 30 Dec 2013 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=36A Pilot Study Investigating Differences in Sleep and Life Preoccupations in Chronic and Acute ...http://www.sleepmedres.org/journal/view.php?number=39
<sec>
<title>Background and Objective</title>
<p>Theory suggests that during the transition from acute to chronic insomnia a shift in attention, from life events to sleep difficulties, occurs. The aim of this study was to examine whether this shift indeed exists, by measuring the frequency and type of preoccupations in acute and chronic insomnia.</p></sec>
<sec>
<title>Methods</title>
<p>Using a cross-sectional design, two groups [people with acute insomnia (n = 11) and chronic insomnia (n = 20)] completed a series of standardized and semi-idiosyncratic measures daily, over the period of one week. They also wore actigraphs to provide objective measures of sleep parameters.</p></sec>
<sec>
<title>Results</title>
<p>Findings suggest no differences in preoccupation between the two groups but show the acute insomnia group report significantly higher levels of perceived stress. Exploratory analysis suggests a reduction in scores on standardized measures across all participants between time 1 and time 2, and no differences on objectively measured sleep parameters.</p></sec>
<sec>
<title>Conclusions</title>
<p>Results indicate there is no difference between people with acute and chronic insomnia in level, and type, of reported preoccupation and that people with acute insomnia are as preoccupied during the day by both sleep and life events, as people with chronic insomnia. Limitations are discussed and future research questions are considered.</p></sec>Original ArticleMon, 30 Dec 2013 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=39Pattern of Hypnotic Drug Prescription in South Korea: Health Insurance Review and Assessment ...http://www.sleepmedres.org/journal/view.php?number=41
<sec>
<title>Background and Objective</title>
<p>This study aimed to characterize patterns of hypnotic drug prescription based on age and gender using data from the Health Insurance Review and Assessment Service-National Patients Sample (HIRA-NPS) of South Korea.</p></sec>
<sec>
<title>Methods</title>
<p>Using HIRA-NPS data, the “number of tablets of equivalent hypnotic drugs (TEQ)” was defined herein as the number of tablets of triazolam, zolpidem immediate-release form, or zolpidem extended-release form.</p></sec>
<sec>
<title>Results</title>
<p>The proportion of hypnotic medication prescriptions, including triazolam and zolpidem, was 1.47% in the sample population. The proportion was significantly higher among women than men (1.63% vs. 1.29%; p &lt; 0.01). In addition, the proportion of subjects who were prescribed hypnotic drugs increased with age. The mean TEQ per year was significantly higher among women in the 30–39 year old group (p = 0.02), but lower in women of the 70–79 year old group compared to men (p = 0.04). Of the subjects prescribed the drugs, 14.53% were prescribed at least 0.5 TEQ per day, while 5.0% were given at least 1.0 TEQ per day 0.6% at least 2.0 TEQ per day. Such cases were most common among middle-aged patients (30–59 years old).</p></sec>
<sec>
<title>Conclusions</title>
<p>The proportion of hypnotic drug prescriptions increased with patient age and in females. However, the total amount of hypnotics prescribed per year was greatest among males and middle-aged patients.</p></sec>Original ArticleMon, 30 Dec 2013 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=41A Case of Hypertensive Intracerebral Hemorrhage Accompanying Sleep Apneahttp://www.sleepmedres.org/journal/view.php?number=42
<p>Stroke is very common in patients with sleep disordered breathing, especially in the elderly. We report the case of a 26-year-old man who had been referred to us with a sudden left side motor weakness of the body, headache, chronic fatigue, and witnessed sleep apneas. Intracerebral hemorrhage in the right external capsule and putamen was identified upon brain computed tomography. He had hypertension which had not been diagnosed previously. On polysomnography, apnea-hypopnea index was 73.0/h and arousal index was 74.7/h, indicating severe sleep apnea. Continuous positive airway pressure titration was conducted to determine the optimal pressure to alleviate the respiratory disturbances. Treatment with antihypertensive medication reduced blood pressure (BP) from 197/145 mm Hg to 130/80 mm Hg after 10 days of use. Co-treatment with the medication and auto-adjustable positive airway pressure additionally decreased BP to 110/60 mm Hg and normalized respiratory disturbances. In addition to BP, left hemiparesis, morning headache, daytime sleepiness, and chronic fatigue were all improved. Early treatment of OSA could help facilitate the rehabilitation of or recovery of weakness in such patients.</p>Brief CommunicationMon, 30 Dec 2013 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=42Utilizing Cognitive-Behavioral Therapy for Insomnia to Facilitate Discontinuation of Sleep ...http://www.sleepmedres.org/journal/view.php?number=31
<p>Many chronic insomnia patients use sleep medication well beyond the recommended duration, and patients who are hypnotic-dependent encounter several challenges when attempting to discontinue. The current article presents these challenges and reviews studies that have added cognitive-behavioral therapy for insomnia (CBTI) to a gradual tapering program to facilitate discontinuation of hypnotic medication in chronic insomnia patients. The current literature provides substantial support for using CBTI to facilitate discontinuation of hypnotic medication in chronic insomnia patients. Across several randomized clinical trials, the majority of the findings indicate that using CBTI, delivered by a therapist or self-help, along with a supervised or gradual tapering program is superior to tapering only or CBTI only in terms of medication discontinuation. Although these results are promising, it should be noted that the long-term evidence is more equivocal, as over 40% of patients relapse in the need for sleep medication within 2 years, which may highlight the importance of adding follow-up booster sessions in hypnotic-dependent insomniacs. These findings indicate that rather than choosing between CBT and hypnotic medication, clinicians might be better served using both treatment modalities to optimize the relative strengths of each treatment. Such an approach represents a more modern view of treating chronic insomnia patients by using both pharmacological and non-pharmacological tools.</p>Review ArticleMon, 30 Apr 2012 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=31Comparison of Anti-Streptococcal Antibodies in Patients with Narcolepsy and Control Grouphttp://www.sleepmedres.org/journal/view.php?number=27
<sec>
<title>Background and Objective</title>
<p>It has been reported that Streptococcal infection is probably a significant environmental trigger for narcolepsy patients from recent studies. However the relationship between the streptococcal infection and narcolepsy is not clear. The aim of this study is to explore the anti-streptolysin O (ASO) titer in narcolepsy patients and healthy control, and the associations of ASO titer levels and polysomnographic findings.</p></sec>
<sec>
<title>Methods</title>
<p>Sixty two narcolepsy patients and Fifty six healthy controls were recruited at the Sleep Center of St. Vincent’s Hospital. The multiple sleep latency test data and polysomnographic findings from the time of their diagnosis were reviewed. Disease duration was defined as the time between the first symptom and time of blood draw. HLA typing was also performed. Participants were tested for markers of immune response to β hemolytic streptococcus.</p></sec>
<sec>
<title>Results</title>
<p>Results indicated that titers of anti-streptococcal antibodies were not significantly different between patients with narcolepsy and healthy controls. There was no significant difference of ASO titer between the HLA DQB1*0602 positive group and HLA DQB1*0602 negative group. In narcolepsy with cataplexy patients, rapid eye movement sleep latency was significantly shorter in the ASO &gt; 200 group.</p></sec>
<sec>
<title>Conclusions</title>
<p>There is no significant difference of ASO titers between patients with narcolepsy and healthy controls. The association between streptococcal infections and narcolepsy in Asian people may be not as significant as Caucasian people.</p></sec>Original ArticleMon, 30 Apr 2012 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=27Long Term Effects of Continuous Positive Airway Pressure in Obstructive Sleep Apnea Patients: ...http://www.sleepmedres.org/journal/view.php?number=28
<sec>
<title>Background and Objective</title>
<p>Obstructive sleep apnea (OSA) is characterized by repetitive episodes of complete or partial upper airway obstruction during sleep. Although, optimal treatment of OSA with continuous positive airway pressure (CPAP) reduce the number of respiratory events during sleep, and thus improve daytime sleepiness, quality of life, and cardiovascular risk, there are few studies that address the long term effects of CPAP treatment. This study aims to determine the long term effects of positive airway pressure (PAP) in compliant OSA patients.</p></sec>
<sec>
<title>Methods</title>
<p>Forty OSA patients naïve to PAP treatment were included. Polysomnography for apnea-hypopnea index, sleep structure, and desaturation index, blood pressure, Epworth Sleepiness Scale (ESS) for excessive daytime sleepiness, and Beck Depression Inventory (BDI) for depressive mood were initially administered before the PAP treatment and after the long term PAP treatment. We have excluded immediate pneumatic effects of the PAP treatment, by administrating a follow up study after 7 days of PAP treatment withdrawal.</p></sec>
<sec>
<title>Results</title>
<p>A total of 40 (male: 92.5%, mean age: 54.4 ± 10.4 yr) patients were enrolled. The duration of PAP treatment was 3.4 ± 1.4 years. The initial apnea-hypopnea index (AHI) was 50.8 ± 22.6/hr which decreased to 34.4 ± 19.1/hr (p ≤ 0.001). These significant reductions in AHI were seen without Body Mass Index changes (p = 0.707). The sleep architecture revealed no significant changes between the initial and follow up study. The systolic and diastolic blood pressure (DBP) decreased significantly after the long term CPAP treatment (systolic blood pressure pre: 138.5 ± 18.1, post: 122.3 ± 13.7, p ≤ 0.001, DBP pre: 88.7 ± 13.6, post: 78.5 ± 11.1, p ≤ 0.001). ESS and BDI decreased significantly after years of PAP treatment compared to the baseline study (ESS pre: 11.5 ± 5.3, post: 8.3 ± 4.7, p ≤ 0.001, BDI pre: 12.7 ± 11.6, post: 6.3 ± 7.0, p = 0.019).</p></sec>
<sec>
<title>Conclusions</title>
<p>This study confirmed that after years of faithful PAP treatment for OSA, the severity of OSA significantly improved. In addition, blood pressure, daytime sleepiness, and depression levels also decreased significantly.</p></sec>Original ArticleMon, 30 Apr 2012 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=28Results of Tailor-Made Multilevel Surgery in Patients with Obstructive Sleep Apneahttp://www.sleepmedres.org/journal/view.php?number=29
<sec>
<title>Background and Objective</title>
<p>The concept of tailor-made, multilevel surgery, including the nasal cavity, a multiple level of the pharynx, should be required to overcome the collapse at multiple levels of the upper airway because most patients show multilevel airway obstruction. The objective of this study was to evaluate the surgical results when the surgery was performed at the multilevel of the pharynx and in a tailor-made manner in obstructive sleep apnea (OSA) patients with multilevel obstruction in various evaluations of the obstruction site.</p></sec>
<sec>
<title>Methods</title>
<p>This is a retrospective analysis of data prospectively gathered on 86 OSA patients treated with multilevel surgery. Patients were evaluated with a questionnaire preoperatively and postoperatively at 1 month and more than 6 months, respectively. A polysomnography was used to evaluate the surgical results postoperatively at more than 6 months.</p></sec>
<sec>
<title>Results</title>
<p>Postoperative values for the questionnaire of both daytime and nighttime symptoms were significantly reduced after surgery. Daytime sleepiness checked by Epworth Sleepiness Scale (ESS) was significantly improved. The postoperative value of apnea-hypopnea index (AHI) was significantly improved after treatment. When the successful outcome was defined as a postoperative AHI &lt; 5, 43.3% of patients met the criteria. The success rates of surgery among the groups according to severity were not statistically significant.</p></sec>
<sec>
<title>Conclusions</title>
<p>Multilevel surgery in a tailor-made manner shows relatively good results. This can be a solution for OSA patients when medical therapy, including nasal continuous positive airway pressure, is not tolerable. Precise and tenacious evaluation of the obstruction site is the key for increasing surgical success.</p></sec>Original ArticleTue, 30 Oct 2012 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=29Self-Reported Sleep Duration, Daytime Sleepiness, and Caffeine Use in Male and Female Morning ...http://www.sleepmedres.org/journal/view.php?number=32
<sec>
<title>Background and Objective</title>
<p>Previous studies in adults have focused on differences in sleep timing with respect to morning and evening (ME) types, or gender difference in the distribution of ME types. We aimed to examine sleep habits and behaviors (daytime sleepiness and caffeine consumption) of adult ME types, and to examine whether the factors associated with ME type differed between men and women.</p></sec>
<sec>
<title>Methods</title>
<p>Among 1,086 subjects to whom we administered the Korean version of Horne-Ostberg Morningness-Eveningness Questionnaire (MEQ-K), the Korean version of the Epworth Sleepiness Scale (KESS), the Pittsburgh Sleep Quality Index (PSQI) and asked questions about their sleep-wake timing and caffeine use, the data from 911 subjects (age: 38.4 ± 10.9 years, range: 18–88; F : M = 565 : 346) were analyzed. Standard scores of the MEQ were used to categorize the subjects as morning type (MT), evening type (ET) and neither type (NT).</p></sec>
<sec>
<title>Results</title>
<p>In the overall group, results from the PSQI indicated a significantly shorter sleep duration and greater caffeine consumption in ET when compared to those of MT or NT (p &lt; 0.05). This was also found in the subgroup of women (p &lt; 0.01), but not in the subgroup of men. Daytime sleepiness as reported on the KESS was significantly greater in the ET than the NT or MT overall (p &lt; 0.05) and among the women (p &lt; 0.01), but did not reach significance among men.</p></sec>
<sec>
<title>Conclusions</title>
<p>Our study found that ET subjects perceived their sleep quality as poorer than that of MT or NT subjects regardless of gender. We also found that ET women had significantly shorter sleep duration, greater daytime sleepiness, and larger caffeine consumption than MT or NT women, but we did not find the same findings in the men.</p></sec>Original ArticleTue, 30 Oct 2012 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=32Clinical and Polysomnographic Comparison between Narcolepsy without Cataplexy and Idiopathic ...http://www.sleepmedres.org/journal/view.php?number=33
<sec>
<title>Background and Objective</title>
<p>The aim of this study is to compare the clinical, electrophysiological (Polysomnography, PSG; Multiple Sleep Latency Test, MSLT) and biological data (HLA DQB1*0602 typing) in idiopathic hypersomnia with narcolepsy without cataplexy.</p></sec>
<sec>
<title>Methods</title>
<p>80 patients with narcolepsy without cataplexy and 71 patients with idiopathic hypersomnia without a long sleep time were recruited at the Sleep Center of St. Vincent’s Hospital. MSLT data and PSG findings from the time of their diagnosis were reviewed. HLA typing was performed.</p></sec>
<sec>
<title>Results</title>
<p>Results indicated that the idiopathic hypersomnia group showed a significant longer mean sleep latency in MSLT compared with the narcolepsy without cataplexy group. But there was no significant difference in the Epworth Sleepiness Scale (ESS) scores between the two groups. Although HLA positivity of both groups was not statistically significant (p = 0.065), HLA positivity tended to be higher in the narcolepsy without cataplexy group than the idiopathic hypersomnia group. The number of awakenings was slightly higher in the idiopathic hypersomnia group, but there was no statistical significance. The number of spontaneous arousal and total arousal indices was not significantly different between the groups. For the PSG, the idiopathic hypersomnia group showed a significantly longer sleep latency than the narcolepsy without cataplexy group (p = 0.009). REM sleep latency (REML) was significantly shorter in the narcolepsy without cataplexy group compared to the idiopathic hypersomnia group. The percentage of REM (SREM) was significantly higher in the narcolepsy without cataplexy group, and the percentage of the wake time during sleep period (SWT) was significantly lower in the narcolepsy without cataplexy group.</p></sec>
<sec>
<title>Conclusions</title>
<p>There were no significant differences of subjective sleep measures such as ESS, disturbed nocturnal sleep, number of naps, age of onset of hypnagogic hallucination, and age of onset of sleep paralysis between patients with narcolepsy without cataplexy and idiopathic hypersomnia. So, the use of objective tests such as the PSG and MSLT may be inevitable for the differential diagnosis of narcolepsy without cataplexy from idiopathic hypersomnia.</p></sec>Original ArticleTue, 30 Oct 2012 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=33Case Studies of Chronic Insomnia Patients Participating in Group Cognitive Behavioral Therapy ...http://www.sleepmedres.org/journal/view.php?number=34
<sec>
<title>Background and Objective</title>
<p>Pharmacotherapy currently widely used in the treatment of insomnia can be helpful in transient insomnia, but research regarding its effectiveness and safety of long-term use is not enough. Therefore, to complement the limitations of pharmacotherapy in the treatment of patients with insomnia, non-pharmacologic treatment methods (cognitive behavioral therapy, CBT) are used. But CBT for insomnia appear to be costly and time-consuming compared to pharmacotherapy, clinical practice in the field can be difficult to be applied. We took the format of group therapy rather than individual therapy to complement the disadvantages of CBT and now we would like to have a thought into its meaning by reporting the effectiveness of group CBT for insomnia.</p></sec>
<sec>
<title>Methods</title>
<p>Patients were recruited at Sleep Center of St. Vincent’s Hospital, 2 men and 3 women led to a group of five patients. CBT is a treatment for correction factors that cause and maintain insomnia, it includes a variety of techniques such as sleep hygiene education, stimulus control, sleep restriction, relaxation and cognitive therapy. A series of treatment were performed five sessions once a week with a frequency from February to March 2012 and were proceeded for about 1 hour and 30 minutes per session.</p></sec>
<sec>
<title>Results</title>
<p>Results indicated that the subjective quality of sleep and sleep efficiency of all patients improved and Pittsburgh Sleep Quality Index and Beck Depression Inventory were decreased in spite of reducing dose of medication.</p></sec>
<sec>
<title>Conclusions</title>
<p>Like these cases, we can contribute to reduce the time and economic burden by performing group CBT for insomnia rather than individual therapy.</p></sec>Brief CommunicationTue, 30 Oct 2012 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=34Validation of a Walking Wheel Method to Fragment Sleep in Ratshttp://www.sleepmedres.org/journal/view.php?number=30
<sec>
<title>Background and Objective</title>
<p>Many attempts have sought to devise an animal model of sleep fragmentation (SF) to understand the clinical effects of sleep loss, but no study has investigated the usefulness of the walking wheel method to interrupt sleep in rats.</p></sec>
<sec>
<title>Methods</title>
<p>Seven-week-old male Wistar rats were divided into a SF group and an exercise control (EC) group, with five rats in each. SF was achieved with a walking wheel using a 30 s on, 90 s off interval (total walking time 6 h/day). The EC group walked the same distance. Rat multiple sleep latency test was performed to measure sleepiness in rats. Sleep data were collected at baseline, and 4, 12, and 18 days after treatment. Percent (%) time spent awake and in non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, NREM and wake bout number, NREM bout length, and mean sleep latency were analyzed.</p></sec>
<sec>
<title>Results</title>
<p>Numbers of NREM and wake bout were higher in the SF group, whereas the NREM bout length was smaller than in the baseline group. Unlike NREM, REM sleep (%) in the SF group was significantly lower than in the baseline and EC groups. Mean sleep latency was shortened in the SF group compared to the baseline and EC groups. EC did not differ significantly with respect to the amount of sleep time (%), bout number of NREM and wakefulness, NREM bout length, and mean sleep latency, compared to its own baseline.</p></sec>
<sec>
<title>Conclusions</title>
<p>Use of a walking wheel is an effective means of interrupting sleep in rats during a long-term period.</p></sec>Original ArticleMon, 30 Apr 2012 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=30Epidemiological Overview of sleep Disorders in the General Populationhttp://www.sleepmedres.org/journal/view.php?number=14
<p>There are several hundred of epidemiological studies assessing different sleep complaints and disorders in the general population. This article summarizes the main findings of these studies and underlines some of the aspects that still need to be investigated. Insomnia complaint is one of the most studied sleep disturbances. Nearly one third of the general population complains of insomnia but a diagnosis is warranted in only 6% to 15% of the population. Excessive sleepiness is also another frequent complaint. However, its definition and method of assessment are so diverse that it is difficult to have a clear estimate of its prevalence in the general population: prevalence rates are ranging between 4% and 26%. Narcolepsy is a rare disorder with a prevalence averaging 0.04% in the general population. Obstructive Sleep Apnea Syndrome, often associated with insomnia or excessive sleepiness, is found in approximately 2% to 4% of the general population and has a higher prevalence in men than in women. Restless legs syndrome (RLS), depending on how it was assessed, varies from a low 1% in Asian countries to a high 19% in Northern European countries. RLS is higher in women and increases with age. Unfortunately, despite the high prevalence, sleep disorders remain poorly identified; less than 20% of individuals with insomnia are correctly diagnosed and treated. The figures are even lower for excessive sleepiness and RLS with less than 10% correctly diagnosed and treated.</p>Review ArticleSat, 30 Apr 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=14The Effect of Non-Pharmacological Treatment for Psychophysiological Insomnia on Cardiovascular ...http://www.sleepmedres.org/journal/view.php?number=10
<sec>
<title>Background and Objective</title>
<p>Cardiac autonomic regulation is altered in psychophysiological insomnia. We evaluated whether successful non-pharmacological treatment for psychophysiological insomnia could stabilize cardiac autonomic regulation.</p></sec>
<sec>
<title>Methods</title>
<p>Subjects were 26 patients with psychophysiological insomnia who underwent four sessions of non-pharmacological treatment. We measured subjects’ heart rate variability (HRV) at baseline and post-treatment. Based on the post-treatment Insomnia Severity Index (ISI) score, we categorized subjects into responder (n = 16, post-ISI &lt; 8) and non-responder (n = 10) groups.</p></sec>
<sec>
<title>Results</title>
<p>At baseline, we found no significant differences between responder and non-responder groups in age, sex, body mass index, insomnia severity, and features of HRV time and frequency domains. In the responders group, we observed significant increases in the standard deviation of the normal sinus to normal sinus interval (SDNN) (p = 0.02), the proportion of the number of interval differences of successive normal sinus to normal sinus intervals greater than 50 ms by the total number of normal sinus to normal sinus intervals (pNN50) (p = 0.02), total power (p &lt; 0.01), and very low frequency (p = 0.02) and a significant decrease in low frequency (p = 0.04) after successful non-pharmacological treatment for insomnia. However, in the non-responders group, there were no significant changes in HRV features after treatment.</p></sec>
<sec>
<title>Conclusions</title>
<p>The successful non-pharmacological treatment of insomnia may reduce the risk of cardiovascular complications in patients with psychophysiological insomnia.</p></sec>Original ArticleSat, 30 Apr 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=10How Do Restless Legs Syndrome Patients Recognize Daytime Sleepiness? - The Multiple Sleep ...http://www.sleepmedres.org/journal/view.php?number=22
<sec>
<title>Background and Objective</title>
<p>Restless legs syndrome induces sleep fragmentation and impairs sleep quality. Although insomnia is the most frequently reported symptom, a substantial proportion of patients report excessive daytime sleepiness (EDS), and the factors that contribute to EDS need to be assessed for optimal treatment.</p></sec>
<sec>
<title>Methods</title>
<p>Sixty-five untreated idiopathic restless legs syndrome (RLS) patients underwent polysomnography (PSG), multiple sleep latency test (MSLT) and the suggested immobilization test (SIT). After excluding nine patients with more than two sleep onset REM (SOREM) in the MSLT, and 15 patients with an apnea-hypopnea index of ≥ 10/hr, 41 patients were finally included. The severity of EDS was evaluated using the Epworth sleepiness scale (ESS), and the severity of RLS by International RLS Study Group Rating Scale (IRLS), and SIT. RLS patients were sub-grouped into sleepy RLS (S-RLS) (ESS &gt; 10), and non-sleepy RLS (NS-RLS) (ESS ≤ 10).</p></sec>
<sec>
<title>Results</title>
<p>The mean age upon evaluation was 54.56 ± 11.91 years of age (female: 70.7%), and the duration of RLS before diagnosis was 11.87 ± 10.65 years. RLS patients had decreased sleep efficiency, increased arousal indexs, increased periodic limb movements during sleep (PLMS) index, and movement arousal index (MAI) by PSG. There were nine patients (22%) in the S-RLS group, and 32 patients (78%) in the NS-RLS group. IRLS severity was significantly higher in the S-RLS than in the NS-RLS group (p = 0.023). The seven patients with SOREM had a mean REM latency of 2.81 ± 5.4. Correlation analysis revealed a negative correlation between the MSLT mean sleep latency and the PLMS index (p = 0.003, ρ = 0.463) and MAI (p = 0.040, ρ = 0.334).</p></sec>
<sec>
<title>Conclusions</title>
<p>EDS is frequent in RLS-PLMS patients and subjective sleepiness was found to be higher in patients that reported severe RLS symptoms.</p></sec>Original ArticleSat, 31 Dec 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=22A Single Center Study of the Clinical Features and Comorbidities of Patients with Restless Legs ...http://www.sleepmedres.org/journal/view.php?number=23
<p>This study investigated the clinical features and comorbidities of patients with restless legs syndrome (RLS). A total of 128 RLS patients (68 women, 60 men; mean age = 58.03 ± 12.58 years) were assessed. The severity of RLS was evaluated by the International RLS Study Group (IRLSSG) Severity Scale. Among the subjects with RLS, depressive symptoms (65.5%) and poor sleep quality (95.4%) were frequently reported, and 88.3% of the patients showed moderate-to-severe symptom severity on the IRLSSG Severity Scale. The most common complaint was insomnia (70.3%), and 16 patients (12.5%) reported leg discomfort as their main symptom. Obstructive sleep apnea was observed in 66% of RLS patient. Iron deficiency was not prevalent in RLS patients. The severity of RLS was not significantly correlated with depression, sleep quality or sleepiness. We conclude that when assessing insomnia patients, RLS symptoms should be evaluated.</p>Brief CommunicationSat, 31 Dec 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=23Effects of Cynanchum Wilfordii Hemsley Extract on the Sleep-Wake Architectures in Ratshttp://www.sleepmedres.org/journal/view.php?number=12
<sec>
<title>Background and Objective</title>
<p>Although <italic>Cynanchum wilfordii</italic> Hemsley <italic>(C. wilfordii)</italic> has been widely used for treating insomnia in Korea, there are no objective data on its sleep-enhancing effects.</p></sec>
<sec>
<title>Methods</title>
<p>We examined the effects of this extract on sleep latency, sleep parameters, and NREM delta activity in rats administered several different dosages (300 mg/kg, 1 g/kg or 3 g/kg, p.o.) and compared them to valerian extract which is a popular natural hypnotic.</p></sec>
<sec>
<title>Results</title>
<p>We found no significant shortening of sleep latency was observed with any dosage of either <italic>C. wilfordii</italic> extract or with valerian. NREM sleep increased significantly at <italic>C. wilfordii</italic> dosages of 300 mg/kg and 1 g/kg but not for 3 g/kg. Only the 1 g/kg dosage significantly decreased the amount of wakefulness. Neither any of the <italic>C. wilfordii</italic> dosages nor valerian extract produced any effect on REM sleep amount.</p></sec>
<sec>
<title>Conclusions</title>
<p>Therefore, <italic>C. wilfordii</italic> could be a useful natural hypnotic with a sleep-enhancing effect.</p></sec>Original ArticleSat, 30 Apr 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=12Clinically Different Phenotypes of Obstructive Sleep Apnea according to 24 Hours Heart Rate ...http://www.sleepmedres.org/journal/view.php?number=11
<sec>
<title>Background and Objective</title>
<p>Heart rate vatiability (HRV) parameters are altered during sleep in patients with obstructive sleep apnea (OSA). Nondipping of nocturnal heart rate during sleep is characteristic, but not all patients with OSA show this. The aim of this study was to identify differences in OSA patients with or without nocturnal heart rate dipping.</p></sec>
<sec>
<title>Methods</title>
<p>We retrospectively reviewed patients (n = 40) who were confirmed to have OSA [4% Oxygen desaturation index (ODI4) &gt; 5/hr) by a simplified sleep study and underwent a 24 hours Holter electrocardiogram. The OSA patients were compared with control subjects (n = 72), who had been found to have no significant medical diseases.</p></sec>
<sec>
<title>Results</title>
<p>Most HRV parameters were lowered in OSA patients [standard deviation of all normal R-R intervals (SDNN): 99.23 vs. 149.06 ms: p &lt; 0.0001]. The OSA patients were divided to two subgroups according to their 24 hours HR tachogram patterns. A HR nondipper subgroup (n = 18) showed a marked decrease in SDNN when compared with a HR dipper subgroup (n = 22)(SDNN 71.72 vs. 121.72 ms: p &lt; 0.0001). SDNN was not associated with a severity index of OSA (ODI4)(r = −0.15, p = 0.3619).</p></sec>
<sec>
<title>Conclusions</title>
<p>In the OSA patients, most HRV parameters (SDNN, standard deviation of the average normal R-R intervals for each 5-min period (SDANN), percentage of adjacent cycles that are &gt; 50 ms apart (pNN50%), root mean square successive differences in milliseconds were lower than in the control subjects. The OSA patients can be divided to two subgroups according to a 24 hours HR tachogram patterns (HR dipper and nondipper). In HR nondipper OSA subgroup, HRV parameters (SDNN, SDANN), Mean SaO2 and basal heart rate during sleep were markedly lowered, but were not associated with an OSA severity (ODI4).</p></sec>Original ArticleSat, 30 Apr 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=11Effects of Sleep Disturbance on the Inducibility of Atrial Fibrillation in Ratshttp://www.sleepmedres.org/journal/view.php?number=15
<sec>
<title>Background and Objective</title>
<p>The association of sleep disturbance (SD) with cardiovascular disease is through its induction of autonomic dysregulation and inflammation, which also could be important pathophysiological mechanisms responsible for atrial fibrillation (AF). However, no study has fully elucidated the causal relationship between SD and AF. We investigated whether SD influences AF vulnerability in an <italic>in vivo</italic> rat model.</p></sec>
<sec>
<title>Methods</title>
<p>We divided 8-week-old Wister rats into 5 groups: 1) control, 2) 3-day SD, 3) 7-day SD, 4) 3-day sham SD, and 5) 7-day sham SD (n = 5 in each group), using the multiple platform method to create SD. We measured baseline heart rate, blood pressure (BP), and AF inducibility via burst atrial pacing (30 mA, 40 Hz, 30 seconds) by means of a transoesophageal electrode and used Sirius red staining to assess collagen deposition in the atriums.</p></sec>
<sec>
<title>Results</title>
<p>Baseline heart rate, diastolic BP and AF inducibility were significantly higher in the SD groups than in the control and sham condition groups (p &lt; 0.05). However, there were no differences between the 3- and 7-day SD groups. Systolic BP and induced AF duration did not statistically differ among any of the experimental groups. The Sirius red staining showed no differences in collagen deposition among any of the experimental groups.</p></sec>
<sec>
<title>Conclusions</title>
<p>SD resulted in increase of AF inducibility in SD rats, suggesting that SD provides an atrial substrate for AF vulnerability, regardless of the disturbance period. However, induced AF duration showed no significant differences in SD rats.</p></sec>Original ArticleSat, 30 Apr 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=15Possibilities for Increasing the Success Rate in Sleep Surgeryhttp://www.sleepmedres.org/journal/view.php?number=13
<p>Sleep surgery for the treatment of obstructive sleep apnea (OSA) has been controversial, due to the many aspects of sleep surgery that remain unknown. Sleep medicine doctors and sleep surgeons may have different viewpoints on the subject, but their goals should be the same: to treat their patients. No one treatment method is the only method for treating all OSA patients. Sleep surgery has many limitations, such as imperfect evaluation methods for finding obstruction sites, the lack of exact indicator for each surgery, etc. Overcoming these limitations should increase sleep surgery’s success rate. In this paper, I discuss the nature of these limitations and what the focus of study should be regarding sleep surgery.</p>Brief CommunicationSat, 30 Apr 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=13Effect of Zolpidem and Enhanced Expiratory Rebreathing Space on Complex Sleep Apneahttp://www.sleepmedres.org/journal/view.php?number=16
<p>Treatment-emergent central sleep apnea has been referred to as ‘complex sleep apnea’, where apparently obstructive respiratory events convert to central apneas with application of positive airway pressure. Potential contributing factors may include increased propensity for arousals and positive airway pressure-induced reductions in CO<sub>2</sub> which amplifies unstable ventilatory control. Here we demonstrate the dramatic beneficial effects of zolpidem and enhanced expiratory rebreathing space on complex sleep apnea, which helps to elude the mechanism of complex sleep apnea.</p>Images In Sleep MedicineSat, 30 Apr 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=16Immunological and Genetic Aspects of Narcolepsyhttp://www.sleepmedres.org/journal/view.php?number=17
<p>Narcolepsy has long been known to be associated with specific Human Leukocyte Antigen variants, and therefore expected to be an autoimmune disorder. For many years, it proved difficult to detect evidence of such a process, but recent studies are making progress on genetic susceptibility factors, as well as potential environmental triggers. New results are also emerging on the presence of specific autoantibodies in the disorder, as well as phenotypic and potential pathophysiologic overlap with other autoimmune disorders. These results are the focus of this review.</p>Review ArticleWed, 31 Aug 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=17Change in Individual Chronotype Over a Lifetime: A Retrospective Studyhttp://www.sleepmedres.org/journal/view.php?number=18
<sec>
<title>Background and Objective</title>
<p>Sleep disturbances resulting from a mismatch between the sleep-wake schedule and an individual’s chronotype can influence work or school performance and numerous health outcomes. Individual chronotype can be determined by genetic factors, and is influenced by environmental factors which could change throughout life. We aimed to examine self-reported changes in chronotype during three different periods of life (childhood, teenage years, and adulthood).</p></sec>
<sec>
<title>Methods</title>
<p>Three hundred forty-three (age: 37.8 ± 11.6 years, range: 18–82; F: M = 214: 129) adult visitors to a National Museum in Korea were recruited for this study. The Korean version of the Horne-Östberg Morningness-Eveningness Questionnaire (MEQ-K) was administered and standard MEQ-K scores were used to categorize subjects as morning type (MT), evening type (ET), or neither type (NT). Binary logistic regression analyses were applied to examine the relationships of gender, current age, and childhood/teenager ME type with change in chronotype between childhood, teenage years, and adulthood.</p></sec>
<sec>
<title>Results</title>
<p>The ages, gender distribution, and years of education were different between the chronotype groups (p &lt; 0.01). Individuals who reported childhood MT or ET had a lower probability of changing their chronotype between childhood and their teenage years compared with individuals reporting childhood NT (p &lt; 0.0001), whereas individuals reporting teenage MT or ET had a higher probability (p &lt; 0.0001). Furthermore, older individuals had a lower probability of reporting a chronotype change between childhood or teenage years and adulthood (p &lt; 0.01).</p></sec>
<sec>
<title>Conclusions</title>
<p>Most individuals reported the same chronotype from childhood to their teenage years but a different chronotype between the teenage years and adulthood. Older age was associated with a lower probability of reporting a different chronotype during childhood or teenage years.</p></sec>Original ArticleWed, 31 Aug 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=18Perceived Stress, Depression, and Coping Strategies in Patients with Sleep-Related Breathing ...http://www.sleepmedres.org/journal/view.php?number=19
<sec>
<title>Background and Objective</title>
<p>This study examined coping strategy frequencies among patients with sleep-related breathing disorder (SRBD) and how the coping strategies related to patients’ respiratory disturbance indices, daytime sleepiness complaints, perceived stress, and depressive mood.</p></sec>
<sec>
<title>Methods</title>
<p>Participants were 170 SRBD patients (Males, 132; Females, 38) and 71 healthy controls (Males, 42; Females, 29). All participants completed questionnaires that assessed daytime sleepiness, perceived stress, depressive mood, and coping styles. Nocturnal polysomnography confirmed all patients as having SRBD.</p></sec>
<sec>
<title>Results</title>
<p>The SRBD patients complained of significantly more daytime sleepiness, higher perceived stress, and more depressive mood compared to controls. We found no significant differences between patient and control groups in how often participants used each coping strategy. Both groups used significantly more problem-focused than emotion-focused coping strategies. However, those who complained of greater sleepiness, perceived higher stress, and/or had more severe depressive mood used greater levels of emotion-focused than problem-focused coping, compared to their counterparts.</p></sec>
<sec>
<title>Conclusions</title>
<p>These findings suggest SRBD patients reporting excessive daytime sleepiness experienced greater stress and felt more depressed. The study also suggests those who complained of greater sleepiness, perceived higher stress, and/or reported more depressive mood coped less effectively, by using emotion-focused coping strategies more often, at the time of these measurements.</p></sec>Original ArticleWed, 31 Aug 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=19Subjective and Objective CPAP Compliance in Patients with Obstructive Sleep Apnea Syndromehttp://www.sleepmedres.org/journal/view.php?number=20
<sec>
<title>Background and Objective</title>
<p>This study aimed to investigate objective and subjective continuous positive airway pressure (CPAP) compliance in patients with obstructive sleep apnea syndrome (OSAS). Moreover, we evaluated the factors and benefits associated with good CPAP compliance.</p></sec>
<sec>
<title>Methods</title>
<p>Subjects were 153 OSAS patients who underwent polysomnography for CPAP titration. Subjective compliance was defined as reported CPAP use of at least 4 hours a day for five or more days per week, and objective compliance was defined as CPAP use of at least 4 hours a day for more than 70% of the time recorded in the CPAP machine.</p></sec>
<sec>
<title>Results</title>
<p>The subjective and objective compliance rates were 34.0% and 20.7%, respectively. Subjectively compliant patients had lower minimum O<sub>2</sub> saturation and higher % of time with O<sub>2</sub> saturation lower than 90% than did patients declining CPAP treatment. Objectively compliant patients had lower insomnia and depression score and lower minimum O<sub>2</sub> saturation than did patients declining CPAP treatment. Daytime sleepiness and subjective sleep quality improved to the same extent in both objectively and subjectively compliant patients.</p></sec>
<sec>
<title>Conclusions</title>
<p>Lower insomnia score and more severe OSA correlate with good CPAP compliance. CPAP effect was comparable between subjectively and objectively compliant patients.</p></sec>Original ArticleWed, 31 Aug 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=20A Case of Nocturnal Stridor with Combined Obstructive Sleep Apnea Caused by Bilateral Vocal ...http://www.sleepmedres.org/journal/view.php?number=21
<p>Bilateral vocal cord palsy is an uncommon medical condition to cause nocturnal stridor and obstructive sleep apnea. We describe the case of a man who had been referred to us with a 20-year history of snoring, witnessed apneas, excessive daytime sleepiness, harsh high-pitched stridor during sleep caused by undiagnosed bilateral vocal cord palsy. Nocturnal polysomnography found that his apnea/hypopnea index was 25 and his minimum arterial oxygen saturation level was 88%. He had of a little bit macroglossia. However, enlarged tonsils or other anatomic abnormalities regarding his oral cavity did not occur to him. Our investigation using flexible fiberoptic laryngoscope revealed that he did indeed have nocturnal stridor combined with obstructive sleep apnea (OSA) due to idiopathic bilateral vocal cord paralysis. Tracheostomy was performed under local anesthesia, and his sleep related problems were resolved immediately. During 2 years of follow-up, no recurrence of apnea, snoring was noted. Laryngeal examination should be performed routinely to evaluate the glottis structure and cause of sleep related stridor and OSA.</p>Brief CommunicationWed, 31 Aug 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=21The Natural History of Insomnia: What We Know, Don’t Know, and Need to Knowhttp://www.sleepmedres.org/journal/view.php?number=24
<p>To date, studies of the natural history of insomnia have focused on the prevalence, incidence, and persistence of chronic insomnia. While these studies have provided seminal information about the epidemiology of insomnia, no studies to date, have been conducted in a manner to 1) allow for a close resolution of the “transitions” from good sleep to acute insomnia, from acute insomnia to the recovery of good sleep, or from acute insomnia to chronic insomnia and/or 2) allow for a comprehensive assessment of the factors that have been theorized to mediate or moderate these transitions.<xref ref-type="bibr" rid="b1-smr-2-3-79">1</xref>–<xref ref-type="bibr" rid="b4-smr-2-3-79">4</xref> The present paper provides a review of these issues and sets forth a research agenda.</p>Review ArticleSat, 31 Dec 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=24The Reliability and Validity of the Korean Version of the Medical Outcomes Study-Sleep Scale in ...http://www.sleepmedres.org/journal/view.php?number=25
<sec>
<title>Background and Objective</title>
<p>We developed a Korean version of the Medical Outcomes Study-Sleep Scale (MOS-Sleep) and confirmed its psychometric properties in patients with obstructive sleep apnea (OSA).</p></sec>
<sec>
<title>Methods</title>
<p>Data were collected from 735 patients with suspected OSA (82.9% male; mean age 47.86 years, range 18–84 years). We assessed internal consistency, test-retest reliabilities, factor analysis, multitrait scaling analysis, and concurrent validity. For assessing concurrent validity, patients were administered the Epworth Sleepiness Scale, Sleep Hygiene Index, Short Form-36 Health Survey (SF-36), Beck Depression Inventory (BDI), Multidimensional Fatigue Inventory (MFI), State-Trait Anxiety Inventory (STAI), and Sleep Disordered Breathing Symptom Questionnaire.</p></sec>
<sec>
<title>Results</title>
<p>Cronbach’s alpha coefficient for all domains and summary indices except Sleep Adequacy exceeded the 0.70 standard for internal consistency reliability. Test-retest reliability was acceptable (r = 0.47–0.87). Six factors were identified by factor analysis. These were the same as those in the original MOS-Sleep. Item convergent and discriminant validities were demonstrated in multi-item domains and indices. Correlations between the MOS-Sleep and other instruments administered in this study provided evidence for construct validity. The 9-item Sleep Problems Index-2 was significantly correlated with SF-36 (r = 0.575), MFI (r = 0.568), BDI (r = 0.499) and STAI (r = 0.435). MOS-Sleep was significantly correlated with subjective severity of OSA.</p></sec>
<sec>
<title>Conclusions</title>
<p>The Korean version of MOS-Sleep has internal consistency, test-retest reliability, and construct validity comparable with the original version.</p></sec>Original ArticleSat, 31 Dec 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=25Polysomnographic Parameters Related to Daytime Sleepiness in Obstructive Sleep Apnea Syndrome: ...http://www.sleepmedres.org/journal/view.php?number=26
<sec>
<title>Background and Objective</title>
<p>Daytime sleepiness is frequently observed in patients with obstructive sleep apnea syndrome (OSAS). The aim of the present study is to assess the parameters that are related to daytime sleepiness in OSAS.</p></sec>
<sec>
<title>Methods</title>
<p>We included patients with OSAS who underwent overnight polysomnography (PSG) followed by a next-day multiple sleep latency test (MSLT) and Epworth Sleepiness Scale (ESS) measurement. The respiratory disturbance index (RDI) was used for diagnosis and assessment of the disease severity.</p></sec>
<sec>
<title>Results</title>
<p>A total of 34 patients were evaluated, among whom 85.3% were male and the other 14.7% female. The mean value of the mean sleep latency (MSL) in the MSLT was 6.27 ± 3.67 minutes (range 1.70–13.40, median 5). We divided patients into two groups according to their median MSL value. The sleepier group exhibited a higher body-mass index (BMI; 27.04 ± 4.20 versus 24.59 ± 2.12), shorter rapid eye movement (REM) sleep latency (80.21 ± 28.61 min. versus 119.44 ± 55.91 min.), greater sleep efficiency (88.82 ± 6.37% versus 82.43 ± 10.43%), and higher respiratory event-related arousal index scores (RERAI; 3.92 ± 2.3/h versus 2.4 ± 1.85/h) than the less sleepy group. RDIs, apnea/hypopnea indices and oxygen saturations did not differ between the groups. Total ESS scores were also not different significantly.</p></sec>
<sec>
<title>Conclusions</title>
<p>A higher BMI, shorter REM latency, relatively higher sleep efficiency and a higher RERAI in the PSG were related to shorter MSL in the MSLT and thus daytime sleepiness in OSAS patients.</p></sec>Original ArticleSat, 31 Dec 2011 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=26Sleep Medicine: Common Quest to Understand the Essential Ingredienthttp://www.sleepmedres.org/journal/view.php?number=5
EditorialTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=5The Correlation between Clinical Variables and Sleep Onset Rapid Eye Movement Period ...http://www.sleepmedres.org/journal/view.php?number=2
<sec>
<title>Background and Objective</title>
<p>A diagnosis of narcolepsy is defined by less than 8 minutes of mean sleep latency, and two or more sleep onset rapid eye movement periods on the Multiple Sleep Latency Test. This study examined the relationship between the sleep onset rapid eye movement period frequencies during Multiple Sleep Latency Test and narcoleptic symptom severity.</p></sec>
<sec>
<title>Methods</title>
<p>From March 2004 to August 2009, 126 patients suffering from excessive daytime sleepiness who visited the Sleep Disorders Clinic of St. Vincent’s Hospital at the Catholic University of Korea were tested by polysomnography and Multiple Sleep Latency Test. Subjects were divided into three groups according to the number of sleep onset rapid eye movement periods that appeared on the Multiple Sleep Latency Test. Symptom severity instruments included the Epworth Sleepiness Scale and the Stanford Center for Narcolepsy Sleep Inventory, and various sleep parameters. In addition, we performed human leukocyte antigen genotyping for human leukocyte antigen-DQB1*0602 on all patients.</p></sec>
<sec>
<title>Results</title>
<p>Among the three groups classified by the number of sleep onset rapid eye movement periods during Multiple Sleep Latency Test, we found no significant differences in demographic features, Epworth Sleepiness Scale, and most polysomnographic findings. However, we observed cataplexy, hypnagogic hallucination, sleep paralysis, and human leukocyte antigen-DQB1*0602 positivity more frequently in groups with higher sleep onset rapid eye movement period frequencies. In addition, the proportions of stage II sleep, REM sleep latency from polysomnography, and mean sleep latency and mean REM sleep latency from the Multiple Sleep Latency Test significantly decreased with increasing sleep onset rapid eye movement period frequency.</p></sec>
<sec>
<title>Conclusions</title>
<p>In this study, we demonstrated that sleep onset rapid eye movement period frequency during Multiple Sleep Latency Test correlated with sleep architecture, daytime symptom severity, and frequency of human leukocyte antigen-DQB1*0602 positivity in narcolepsy. Further studies are needed to explore the pathophysiology of narcolepsy associated with sleep onset rapid eye movement periods.</p></sec>Original ArticleTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=2Sleep Medicine: A Growing Field in the Scientific Worldhttp://www.sleepmedres.org/journal/view.php?number=1
EditorialTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=1Preserved Sleep Quality under Simulated Altitude as Assessed by Electroencephalography Power ...http://www.sleepmedres.org/journal/view.php?number=3
<sec>
<title>Background and Objective</title>
<p>Simulated altitude as a model for hypoxia has shown inconsistent results in terms of impaired cognition. We hypothesized that preserved periods of stable sleep even under hypoxia could explain stable cognitive function. Delta spectral power on electroencephalography during stable sleep as well as high frequency coupling on the electrocardiogram-based spectrogram was adopted as measures of sleep quality.</p></sec>
<sec>
<title>Methods</title>
<p>Eleven healthy, non-smoking subjects (7 men, 27 ± 1.5 years) were exposed to 9 hours of continuous hypoxia for 13 consecutive nights. Polysomnography was done at baseline and during 3 time points, at night 3, 7, and 14. In each study, delta spectral power was obtained during stable N2 and N3 sleep. Stable sleep was defined when there was no significant fragmentation in electroencephalography and fluctuation in electromyography and cardiorespiratory signals. The time threshold was 2 or 5 continuous minutes for N2 and 2 minutes for N3. The amount of high frequency coupling for the sleep period on the electrocardiogram-based spectrogram was computed. Randomized block ANOVA was used with electroencephalography delta power and high frequency coupling as dependent variables with post hoc Tukey test.</p></sec>
<sec>
<title>Results</title>
<p>Delta spectral power during stable sleep was not significantly different across the entire hypoxic exposures (p = 0.98 for N2; p = 0.32 for N3). High frequency coupling was different between pre-exposure and mid-exposure (night 7; 52.5 ± 23.6% vs. 39.0 ± 16.7%, p = 0.02) but returned to the baseline level at the post-exposure (night 14; 45.4 ± 18.2%, p = 0.39).</p></sec>
<sec>
<title>Conclusions</title>
<p>Both preservation of the proportion of stable sleep and unchanged delta power during these periods may help explain maintained cognition in conditions of chronic nocturnal hypoxic exposures.</p></sec>Original ArticleTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=3Outcome of Continuous Positive Airway Pressure Treatment with Suboptimal Pressure in ...http://www.sleepmedres.org/journal/view.php?number=6
<p>Continuous positive airway pressure is the treatment of choice for obstructive sleep apnea, and is highly effective especially in moderate-to-severe obstructive sleep apnea. Although continuous positive airway pressure treatment with optimal pressure is ideal, some patients undergo continuous positive airway pressure treatment with suboptimal pressure. We aimed to evaluate the treatment outcome of continuous positive airway pressure with suboptimal pressure in obstructive sleep apnea. In this study, although mean apnea-hypopnea index was reduced after 3 and 6 months of continuous positive airway pressure treatment with suboptimal pressure compared to that of diagnostic polysomnography, continuous positive airway pressure treatment with suboptimal pressure is effective to reduce mean apnea-hypopnea index to less than 5 only in 53.85% after 3 months of continuous positive airway pressure treatment, and 60% of patients after 6 months of continuous positive airway pressure treatment, respectively.</p>Brief CommunicationTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=6A New Horizon of Sleep Medicine Researchhttp://www.sleepmedres.org/journal/view.php?number=4
EditorialTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=4Methylphenidate’s Effect on Cerebral Blood Flow in Patients with Narcolepsyhttp://www.sleepmedres.org/journal/view.php?number=7
<p>We performed <sup>99m</sup>Tc-ethyl cysteinate dimer brain single-photon emission computed tomography before and after administering methyl-phenidate, for four weeks, to narcolepsy patients with cataplexy. Cerebral blood flow increased in the bilateral cingulate gyri and both thalami with methylphenidate treatment as compared to pre-methylphenidate treatment. methylphenidate treatment also produced an regional cerebral blood flow increase in the bilateral nucleus accumbens, cingulate gyri, superior frontal gyri, and bilateral amygdalo-hippocampi and parahippocampal gyri as compared to pre-methylphenidate treatment. Moreover, no brain region showed a significant regional cerebral blood flow decrease after methylphenidate treatment.</p>Images in Sleep MedicineTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=7Obstructive Sleep Apnea and Neurocognitive Functionhttp://www.sleepmedres.org/journal/view.php?number=8
<p>Declines in various domains of neurocognitive function are observed in patients with obstructive sleep apnea, and these declines may be reversible with continuous positive airway pressure. However, upon reviewing the literature, a majority of the current studies are limited by small sample sizes and study design constraints. Additional large-scale, randomized clinical trials are needed to explore these relationships as well as to assess the etiology of the neurocognitive decline in obstructive sleep apnea patients and to determine which neurocognitive domain is most affected by obstructive sleep apnea and reversible by continuous positive airway pressure.</p>ReviewTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=8A Polysomnography Study of Snoring and Obstructive Sleep Apnea in Relation to Chronic Bronchitishttp://www.sleepmedres.org/journal/view.php?number=9
<sec>
<title>Background and Objective</title>
<p>Reportedly, snoring is associated with chronic bronchitis. This association warrants further studies including polysomnographic evaluations because of few epidemiologic studies on the association. Via a polysomnography study, we evaluated the associations of snoring, obstructive sleep apnea, and systemic inflammation with chronic bronchitis among 442 participants from a population-based cohort.</p></sec>
<sec>
<title>Methods</title>
<p>At baseline, we assessed participants’ serum levels of C-reactive protein, a biomarker of systemic inflammation. Over a 5-year period, we conducted overnight polysomnography and identified any new cases of chronic bronchitis.</p></sec>
<sec>
<title>Results</title>
<p>After taking into account age, smoking, and other potential risk factors, the multivariate odds ratio (95% CI) for chronic bronchitis was 2.9 (95% CI, 1.3–6.4) for snorers with cumulative duration of snoring episodes ≥ 1 hour as compared with those snoring &lt; 1 hour. This association did not change after further adjustment for the presence of apnea. Obstructive sleep apnea had no association with chronic bronchitis. A higher level of serum C-reactive protein was associated with chronic bronchitis (p value for trend &lt; 0.05). In a joint analysis of snoring and C-reactive protein, longer cumulative duration of snoring episodes accompanied by systemic inflammation was associated with a 10-fold (95% CI, 2.9 to 37.4) increase in the multivariate odds of chronic bronchitis.</p></sec>
<sec>
<title>Conclusions</title>
<p>This polysomnography study provides additional data supporting the hypothesis that snoring is associated with chronic bronchitis implying that snoring-related local and systemic inflammation may play roles in the development of chronic bronchitis.</p></sec>Original ArticleTue, 30 Nov 2010 00:00:00 +0100http://www.sleepmedres.org/journal/view.php?number=9